Replace HAML with SLIM
Update CHANGELOG
Convert to haml
Merge branch 'slim-rails-mauro' into slim-rails

Conflicts:
	lib/pah/files/app/views/application/_flash_messages.html.slim
	lib/pah/files/app/views/layouts/application.html.slim
Some fixes on slim => haml
Merge pull request #311 from Helabs/slim-rails

Slim rails.

Closes #281.