some macro and table renaming to make things clearer
* Data navigation (prev, next, up to set), closes #42

* coming from a set view, it's possible to go back to the set or change
  to previous resp. next data
* order in datalist is preserved (saved as cookie by dataTables)

various:

* README update
* small coffeescript refactoring
* small template changes
* decorator for deleting cookies after a request (not used)
experimenting with comment sections
comment testing contd, console scripts asks for database connection
Set, Data, Entry models support comments

* Commentable as base class for all commentable entities
* set, data, entry inherit from Commentable now

other:

* console scripts asks for database connection
* buildout.cfg updated for testing
* changed alchemy test because of problems with py.test
** still doesn't work, reasons unclear...
** stay with nose
Merge branch 'xx' into dpausp_test
Comment sections are usable now (#35)

* comment section for data and set
* comments are hidden by default
* removed Commentable hierarchy and changed to separate comment classes
** inheritance caused some strange problems...