Implement some markup helpers
Export org source blocks 'css htmlized per default
Simplify sass publishing functions
Simplify coffeescript publishing function
Add font file extensions to asset publisher
Add project name to defaults plist
Ignore sass files with a beginning underscore
Implement org plist functions

The functions (jekel--org-infile-plist) and (jekel--blog-post-plist)
return plists for a specific object via given path. Those are used to
describe the metadata for a blog post, for instance.
Implement (jekel--blog-posts)
Implement (jekel--publish-asset)
Add locally bound jekel-project variable
Use :pretty paths per default
Use the correct infile plist
Fix pub-dir for blog posts and normal org files
Fix key for the default blog post layout
Bind jekel-project and page-time variable for org
Let the helpers compute the correct relative path
Implement (blog-posts) and time formatting helpers