Use valid css class names when pygments language contains invalid chars, eg html+jango
Fix tables alignments in Cucumber features
Remove redundant whitespace in a Cucumber feature
Update history to reflect merge of #2108 [ci skip]
Extract core extensions into a Utils module

Fixes #2111
Add Utils.stringify_hash_keys
Rename those Utils functions.
Use jekyll-sass-converter 1.0.0.rc3
Update history to reflect merge of #2112 [ci skip]
Use the rake helper for mkdir as this version makes two folders on Windows
Update history to reflect merge of #2118 [ci skip]
Properly clean path for Windows machines which is *nix-compliant.
Properly strip drive name from clean path when sanitizing path.
Remove obsolete `normalize_options`.
Trim trailing spaces and convert tabs to spaces.
Update history to reflect merge of #2121 [ci skip]
Update history to reflect merge of #2109 [ci skip]
Update history to reflect merge of #2122 [ci skip]
Update normalize.css to v3.0.0.
Update modernizr to v2.7.1.