First sweep trying to make all references to kylewn customizable

There's some fluff left (e.g. twitter.js). Work in progress...
typos :s
More typos :s
Add custom_* files

(and original Piwik code as example_custom_body_bottom.html)
Merge branch 'master' into dekylify (utf8-safe keys)
Merge pull request #7 from thedod/dekylify

First sweep trying to make all references to kylewm customizable