Update CONTRIBUTING.md

Feature requests should be discussed over the core mailing list.

Author: José Valim

CONTRIBUTING.md

@@ -5,13 +5,18 @@ process easy and effective for everyone involved!
 
 ## Using the issue tracker
 
-The issue tracker is the preferred channel for [bug reports](#bugs-reports),
-[features requests](#feature-requests) and [submitting pull
-requests](#pull-requests), but please **do not** use the issue tracker for
-personal support requests. Instead, use
-[the mailing list](http://groups.google.com/group/elixir-lang-talk),
-[Stack Overflow](http://stackoverflow.com/questions/ask?tags=elixir), or
-[#elixir-lang](irc://chat.freenode.net/elixir-lang) on Freenode).
+Use the issues tracker for:
+
+* [bug reports](#bugs-reports)
+* [submitting pull requests](#pull-requests)
+
+Please **do not** use the issues tracker for personal support requests nor feature requests. Support requests should be send to:
+
+* [the elixir-talk mailing list](http://groups.google.com/group/elixir-lang-talk)
+* [Stack Overflow](http://stackoverflow.com/questions/ask?tags=elixir)
+* [#elixir-lang](irc://chat.freenode.net/elixir-lang)
+
+Feature requests can be discussed on [the elixir-core mailing list](http://groups.google.com/group/elixir-lang-core).
 
 We do our best to keep the issues tracker tidy and organized, making it useful
 for everyone. For example, we classify open issues per application and perceived
@@ -60,10 +65,10 @@ Example:
 
 ## Feature requests
 
-Feature requests are welcome. But take a moment to find out whether your idea
-fits with the scope and aims of the project. It's up to *you* to make a strong
-case to convince the project's developers of the merits of this feature. Please
-provide as much detail and context as possible.
+Feature requests are welcome and should be discussed on [the elixir-core mailing list](http://groups.google.com/group/elixir-lang-core). But take a moment to find
+out whether your idea fits with the scope and aims of the project. It's up to *you*
+to make a strong case to convince the project's developers of the merits of this
+feature. Please provide as much detail and context as possible.
 
 ## Contributing
 
@@ -86,6 +91,10 @@ You can run all tests in the root directory with `make test` and you can
 also run tests for a specific framework `make test_#{NAME}`, for example,
 `make test_ex_unit`.
 
+From time to time, your tests may fail in an existing Elixir checkout and
+may require a clean start by running `make clean compile`. You can always
+check [the official build status on Travis-CI](https://travis-ci.org/elixir-lang/elixir).
+
 With tests running and passing, you are ready to contribute to Elixir and
 send your pull requests.