dannyprose/Middleman-HTML5BP-HAML — pull request #18 by murphyrandle (2013-07-15 17:40:25+00:00)
Title: Simple fixes to gemfile

Bundler requested that source be changed to 'https://rubygems.org'.
Removed the requirement for coffee-filter. According to:

https://github.com/middleman/middleman/issues/813

Coffee-filter is no longer necessary because it's built into HAML 4.
This solved Middleman runtime errors for me.