Rework of how a Filter receives commits

1. remove own paginator implementation and use
   ui.bootstrap paginator

* remove commit list paginator template
* remove commit list paginator directive
* add ui.bootstrap.paginator to filter page
Rework of how a Filter receives commits

2. add a commits worker to receive commits based on
   given filter options
   The worker has a simple cache implementation
   based on the url.
Rework of how a Filter receives commits

3. add a getCommits service
* code formatting
* simplify commit list directive by handling changed
  commit list in controller instead of link function
* remove unnecessary hasNext, hasPrevious and hasFirst member
Rework of how a Filter receives commits

4. add pagination options to filter controller
* remove commit cache handling from Filter
Rework of how a Filter receives commits

5. The filter now receives always all commits of
   a given query. To avoid long ui response time
   the getCommits service provides progress handler,
   this means every time a portion of commits are
   received the Filter is able to populate and ui able
   to render them.

   Now that the Filter always holds all commits the
   Filter itself does a better pagination handling.
   Doesn’t matter if the result has to post process
   the result.
* remove obsolete tests