add formatting to CHANGELOG

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CHANGELOG.md

@@ -20,62 +20,64 @@ attribute scrubbers should they need to address CVE-2018-8048.
 
 ## 2.2.1 / 2018-03-19
 
+### Security
+
 Addresses CVE-2018-8048. Loofah allowed non-whitelisted attributes to be present in sanitized output when input with specially-crafted HTML fragments.
 
 This CVE's public notice is at https://github.com/flavorjones/loofah/issues/144
 
 
 ## 2.2.0 / 2018-02-11
 
-Features:
+### Features:
 
 * Support HTML5 `<main>` tag. #133 (Thanks, @MothOnMars!)
 * Recognize HTML5 block elements. #136 (Thanks, @MothOnMars!)
 * Support SVG `<symbol>` tag. #131 (Thanks, @baopham!)
 * Support for whitelisting CSS functions, initially just `calc` and `rgb`. #122/#123/#129 (Thanks, @NikoRoberts!)
 * Whitelist CSS property `list-style-type`. #68/#137/#142 (Thanks, @andela-ysanni and @NikoRoberts!)
 
-Bugfixes:
+### Bugfixes:
 
 * Properly handle nested `script` tags. #127.
 
 
 ## 2.1.1 / 2017-09-24
 
-Bugfixes:
+### Bugfixes:
 
 * Removed warning for unused variable. #124 (Thanks, @y-yagi!)
 
 
 ## 2.1.0 / 2017-09-24
 
-Notes:
+### Notes:
 
 * Re-implemented CSS parsing and sanitization using the [crass](https://github.com/rgrove/crass) library. #91
 
 
-Features:
+### Features:
 
 * Added :noopener HTML scrubber (Thanks, @tastycode!)
 * Support `data` URIs with the following media types: text/plain, text/css, image/png, image/gif, image/jpeg, image/svg+xml. #101, #120. (Thanks, @mrpasquini!)
 
 
-Bugfixes:
+### Bugfixes:
 
 * The :unprintable scrubber now scrubs unprintable characters in CDATA nodes (like `<script>`). #124
 * Allow negative values in CSS properties. Restores functionality that was reverted in v2.0.3. #91
 
 
 ## 2.0.3 / 2015-08-17
 
-Bug fixes:
+### Bug fixes:
 
 * Revert support for negative values in CSS properties due to slow performance. #90 (Related to #85.)
 
 
 ## 2.0.2 / 2015-05-05
 
-Bug fixes:
+### Bug fixes:
 
 * Fix error with `#to_text` when Loofah::Helpers hadn't been required. #75
 * Allow multi-word data attributes. #84 (Thanks, @jstorimer!)
@@ -84,24 +86,24 @@ Bug fixes:
 
 ## 2.0.1 / 2014-08-21
 
-Bug fixes:
+### Bug fixes:
 
 * Load RR correctly when running test files directly. (Thanks, @ktdreyer!)
 
 
-Notes:
+### Notes:
 
 * Extracted HTML5::Scrub#scrub_css_attribute to accommodate the Rails integration work. (Thanks, @kaspth!)
 
 
 ## 2.0.0 / 2014-05-09
 
-Compatibility notes:
+### Compatibility notes:
 
 * ActionView helpers now must be required explicitly: `require "loofah/helpers"`
 * Support for Ruby 1.8.7 and prior has been dropped
 
-Enhancements:
+### Enhancements:
 
 * HTML5 whitelist allows the following ...
   * tags: `article`, `aside`, `bdi`, `bdo`, `canvas`, `command`, `datalist`, `details`, `figcaption`, `figure`, `footer`, `header`, `mark`, `meter`, `nav`, `output`, `section`, `summary`, `time`
@@ -111,7 +113,7 @@ Enhancements:
 * `Loofah.fragment` accepts an optional encoding argument, compatible with `Nokogiri::HTML::DocumentFragment.parse`. #62 (Thanks, Ben Atkins!)
 * HTML5 sanitizers now remove attributes without values. (Thanks, Kasper Timm Hansen!)
 
-Bug fixes:
+### Bug fixes:
 
 * HTML5 sanitizers' CSS keyword check now actually works (broken in v2.0). Additional regression tests added. (Thanks, Kasper Timm Hansen!)
 * HTML5 sanitizers now allow negative arguments to CSS. #64 (Thanks, Jon Calhoun!)
@@ -124,15 +126,15 @@ Bug fixes:
 
 ## 1.2.0 (2011-08-08)
 
-Enhancements:
+### Enhancements:
 
 * Loofah::Helpers.sanitize_css is a replacement for Rails's built-in sanitize_css helper.
 * Improving ActionView integration.
 
 
 ## 1.1.0 (2011-08-08)
 
-Enhancements:
+### Enhancements:
 
 * Additional HTML5lib whitelist elements (from html5lib 1524:80b5efe26230).
   Up to date with HTML5lib ruby code as of 1723:7ee6a0331856.
@@ -142,15 +144,15 @@ Enhancements:
 
 ## 1.0.0 (2010-10-26)
 
-Notes:
+### Notes:
 
 * Moved ActiveRecord functionality into `loofah-activerecord` gem.
 * Removed DEPRECATIONS.rdoc documenting 0.3.0 API changes.
 
 
 ## 0.4.7 (2010-03-09)
 
-Enhancements:
+### Enhancements:
 
 * New methods Loofah::HTML::Document#to_text and
   Loofah::HTML::DocumentFragment#to_text do the right thing with
@@ -163,23 +165,23 @@ Enhancements:
 
 ## 0.4.4, 0.4.5, 0.4.6 (2010-02-01)
 
-Enhancements:
+### Enhancements:
 
 * Loofah::HTML::Document#text and Loofah::HTML::DocumentFragment#text now escape HTML entities.
 
-Bug fixes:
+### Bug fixes:
 
 * Loofah::XssFoliate was not properly escaping HTML entities when implicitly scrubbing a string attribute. GH #17
 
 
 ## 0.4.3 (2010-01-29)
 
-Enhancements:
+### Enhancements:
 
 * All built-in scrubbers are accepted by ActiveRecord::Base.xss_foliate
 * Loofah::XssFoliate.xss_foliate_all_models replaces use of the constant LOOFAH_XSS_FOLIATE_ALL_MODELS
 
-Miscellaneous:
+### Miscellaneous:
 
 * Modified documentation for bootstrapping XssFoliate in a Rails app,
   since the use of Bundler breaks the previously-documented method. To
@@ -188,33 +190,33 @@ Miscellaneous:
 
 ## 0.4.2 (2010-01-22)
 
-Enhancements:
+### Enhancements:
 
 * Implemented Node#scrub! for scrubbing subtrees.
 * Implemented NodeSet#scrub! for scrubbing a set of subtrees.
 * Document.text now only serializes <body> contents (ignores <head>)
 * <head>, <html> and <body> added to the HTML5lib whitelist.
 
-Bug fixes:
+### Bug fixes:
 
 * Supporting Rails apps that aren't loading ActiveRecord. GH #10
 
-Miscellaneous:
+### Miscellaneous:
 
 * Mailing list is now loofah@librelist.com / http://librelist.com
 * IRC channel is now \#loofah on freenode.
 
 
 ## 0.4.1 (2009-11-23)
 
-Bugfix:
+### Bugfix:
 
 * Manifest fixed. Whoops.
 
 
 ## 0.4.0 (2009-11-21)
 
-Enhancements:
+### Enhancements:
 
 * Scrubber class introduced, allowing development of custom scrubbers.
 * Added support for XML documents and fragments.
@@ -225,20 +227,20 @@ Enhancements:
 
 ## 0.3.1 (2009-10-12)
 
-Bug fixes:
+### Bug fixes:
 
 * Scrubbed Documents properly render html, head and body tags when serialized.
 
 
 ## 0.3.0 (2009-10-06)
 
-Enhancements:
+### Enhancements:
 
 * New ActiveRecord extension `xss_foliate`, a drop-in replacement for xss_terminate[http://github.com/look/xss_terminate/tree/master].
 * Replacement methods for Rails's helpers, Loofah::Rails.sanitize and Loofah::Rails.strip_tags.
 * Official support (and test coverage) for Rails versions 2.3, 2.2, 2.1, 2.0 and 1.2.
 
-Deprecations:
+### Deprecations:
 
 * The methods strip_tags, whitewash, whitewash_document, sanitize, and
   sanitize_document have been deprecated. See DEPRECATED.rdoc for
@@ -247,20 +249,20 @@ Deprecations:
 
 ## 0.2.2 (2009-09-30)
 
-Enhancements:
+### Enhancements:
 
 * ActiveRecord extension scrubs fields in a before_validation callback
   (was previously in a before_save)
 
 
 ## 0.2.1 (2009-09-19)
 
-Enhancements:
+### Enhancements:
 
 * when loaded in a Rails app, automatically extend ActiveRecord::Base
   with html_fragment and html_document. GH #6 (Thanks Josh Nichols!)
 
-Bugfixes:
+### Bugfixes:
 
 * ActiveRecord scrubbing should generate strings instead of Document or
   DocumentFragment objects. GH #5