Document irc channel_key setting

This documentation is to go with https://github.com/travis-ci/travis-core/pull/209
New staff picks!
GitHub pages wut?
Maybe missing a permalink?
Lmao if you forget the _includes directory.
Add proper year.
VMs are 64 bit
VMs are 64 bit
Erlang is 64 bit
VMs are 64 bit
Rearrange the sidebar
Remove everything that's TBD at the moment.
Update erlang.md

Added Dutch tutorial of automatic testing with Erlang and Travis-CI
Merge pull request #268 from wardbekker/master

Added link to extensive Dutch video tutorial
Align signup button properly.
Add full link to travisci.com to the sidebar.

Align the top "logo" and make it the full name.
Merge pull request #253 from rboulton/patch-2

Document irc channel_key setting
Update erlang.md

Added the english translation of the original Dutch article.
Merge pull request #269 from wardbekker/master

English translation of Travis-CI tutorial for Erlang added
added docs for meteor packages support