Initial changelog entry. (#23)

* Initial changelog entry.

* Fix date.

* Update CHANGELOG.md

CHANGELOG.md

@@ -0,0 +1,7 @@
+# Changelog
+
+## 0.3.0 (2019-03-19)
+ * `chai` is no longer exported, and `should` is no longer automatically installed. ([#18](https://github.com/OpenZeppelin/openzeppelin-test-helpers/pull/18))
+
+#### How to upgrade from 0.2
+If you use Chai assertions in your project you should make sure to explicitly install it: `npm install chai`. If you need to access the `chai` instance you should now get it through `require('chai')`. If you use `should`-style assertions you should set it up manually now, by adding `require('chai/register-should')` in your tests, or e.g. in your Truffle config. Check out OpenZeppelin's upgrade commit in case it might be helpful: [`cf7375d`](https://github.com/OpenZeppelin/openzeppelin-solidity/commit/cf7375d6b873afc9f705e329db39e2ef389af9d2).