Update Router helpers documentation in README
Merge pull request #393 from stevedomin/steve-update-readme-router

Update Router helpers documentation in README
Code block for route helpers is terminated too early
Merge pull request #395 from stevedomin/steve-update-readme-router

Code block for route helpers is terminated too early
Document the session plug and move it to new config
Document the parsers plug and move it to new config
Document the static plug and move it to new config

We have also cleaned up and move Phoenix.Project
to Mix.Phoenix so nobody relies on such logic outside
of Mix tasks or Mix specific behaviour (like the code
reloader).
Document the method override plug and move it to new config
Move code reloader configuration to Phoenix environment
Update CHANGELOG
Merge pull request #389 from phoenixframework/jv-config

Clean up compile-time router configuration
remove cs files from priv as they are not required at runtime
Remove unused Phoenix.Plugs
Add Plug.HEAD to the before pipeline, closes #347
Remove previous head routing
capture_log in integration tests
Clean up code reloader
Add phoenix.compile task and prepend to compilers list

Closes #317
Add Important links with new mailing lists 🚀
Add docs badge to README