Feature/libsass

It seems like file globbing is [not specific to grunt-sass](https://github.com/sindresorhus/grunt-sass/issues/115), but it's a [Grunt ability](http://gruntjs.com/configuring-tasks#building-the-files-object-dynamically). Have you tried using globbing (wildcard) patterns here and [line 158](https://github.com/centresource/generator-playbook/pull/49/files#diff-bc4e33eaf0144af469025d16b83126c9R158)?