Add basic support for blog post category listings.
Use existing posts var
Merge pull request #1 from dave-elkan/master

Add basic support for blog post category listings.
Assign posts to variable and use that, instead of the output of Posts
Merge pull request #2 from dave-elkan/master

Assign posts to variable and use that, instead of the output of Posts
Read new format of paths for posts.
Merge branch 'master' of github.com:TravisTheTechie/grunt-markdown-blog