Tags: Created data stuctures for handlings tags. Created a first simple tag view model which is displayed in the document template.
Merge commit 'f2e28ef' into tags
Tags: Added the building block for a tag map renderer
Tags: More steps towards tag maps
Tags: First working tagmap
Add a String method to the Tag type
Tagmap bug fix: Fixed the bug which led to only a single item for each tag
Minor ceanup in the repository item sorter
Sort tags by name
Added a relative and absolute path provider for the item and tag mapper in order to be able to provide a different path for items on the tag map page.
Link tags
Fixed the Remove method for the tag map
Tag map: Added the ability to remove tags from the tag map which have been removed from an item.
Default Theme Update: Remove the bottom margin from the document h1 headline. This moves the H1 headline and the document description closer together and separates them from the content
Default Theme Update: Increased the margin between the description and the content block
Default Theme: Styled the tag map page
Default Theme: Styled the tag list for documents
Default Theme Update: Don't render the childs section if there are no childs
Default Theme: Changed the tag map content template. Display a message if there are not tags.
Roadmap Update. Removed tag links from the roadmap because it is implemented.