docs: Update the readme to point to v4 everywhere

README.md

@@ -1,6 +1,5 @@
 # combine
 [![Build Status](https://travis-ci.org/Marwes/combine.svg?branch=master)](https://travis-ci.org/Marwes/combine)
-[![Docs v3](https://docs.rs/combine/badge.svg?version=^3)](https://docs.rs/combine/^3)
 [![Docs](https://docs.rs/combine/badge.svg)](https://docs.rs/combine)
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@@ -48,15 +47,15 @@ A tutorial as well as explanations on what goes on inside combine can be found i
 
 ## Features
 
-* __Parse arbitrary streams__ - Combine can parse anything from `&[u8]` and `&str` to iterators and `Read` instances. If none of the builtin streams fit your use case you can even implement a couple traits your self to create your own custom [stream](https://docs.rs/combine/3.*/combine/stream/index.html)!
+* __Parse arbitrary streams__ - Combine can parse anything from `&[u8]` and `&str` to iterators and `Read` instances. If none of the builtin streams fit your use case you can even implement a couple traits your self to create your own custom [stream](https://docs.rs/combine/*/combine/stream/index.html)!
 
-* __zero-copy parsing__ - When parsing in memory data, combine can parse without copying. See the [range module](https://docs.rs/combine/3.*/combine/parser/range/index.html) for parsers specialized for zero-copy parsing.
+* __zero-copy parsing__ - When parsing in memory data, combine can parse without copying. See the [range module](https://docs.rs/combine/*/combine/parser/range/index.html) for parsers specialized for zero-copy parsing.
 
 * __partial parsing__ - Combine parsers can be stopped at any point during parsing and later be resumed without losing any progress. This makes it possible to start parsing partial data coming from an io device such as a socket without worrying about if enough data is present to complete the parse. If more data is needed the parser will stop and may be resumed at the same point once more data is available. See the [async example](https://github.com/Marwes/combine/blob/master/examples/async.rs) for an example and [this post](https://marwes.github.io/2018/02/08/combine-3.html) for an introduction.
 
 ## About
 
-A parser combinator is, broadly speaking, a function which takes several parsers as arguments and returns a new parser, created by combining those parsers. For instance, the [many](https://docs.rs/combine/*/combine/fn.many.html) parser takes one parser, `p`, as input and returns a new parser which applies `p` zero or more times. Thanks to the modularity that parser combinators gives it is possible to define parsers for a wide range of tasks without needing to implement the low level plumbing while still having the full power of Rust when you need it. 
+A parser combinator is, broadly speaking, a function which takes several parsers as arguments and returns a new parser, created by combining those parsers. For instance, the [many](https://docs.rs/combine/*/combine/fn.many.html) parser takes one parser, `p`, as input and returns a new parser which applies `p` zero or more times. Thanks to the modularity that parser combinators gives it is possible to define parsers for a wide range of tasks without needing to implement the low level plumbing while still having the full power of Rust when you need it.
 
 The library adheres to [semantic versioning](https://semver.org/).
 
@@ -98,13 +97,9 @@ https://github.com/Marwes/combine/issues/73 contains discussion and links to com
 
 There is an additional crate which has parsers to lex and parse programming languages in [combine-language](https://github.com/Marwes/combine-language).
 
-You can find older versions of combine (parser-combinators) [here](https://crates.io/crates/parser-combinators).
 
 ## Contributing
 
-Current master is the 3.0.0 branch. If you want to submit a fix or feature to the 2.x version of combine then
-do so to the 2.x branch or submit the PR to master and request that it be backported.
-
 The easiest way to contribute is to just open an issue about any problems you encounter using combine but if you are interested in adding something to the library here is a list of some of the easier things to work on to get started.
 
 * __Add additional parsers__ If you have a suggestion for another parser just open an issue or a PR with an implementation.