New DB structures

New DB structures are needed for: prefrences & session
Replaceing old prefrences tables + workspaceState

(from redmine: issue id 2327, created on 2016-04-26 by benjamin.fischer, closed on 2016-05-09)

• Relations:
  • blocks #2296
  • blocks #2300
  • child #2353
  • parent #2294
• Changesets:
  • Revision 2852 by Benjamin Fischer on 2016-05-09T13:30:24Z:

JSONData: implemented common interface to save (key,wsId) json data

this system is now used for storeing preferences (all of them)
closes #2327

• Revision 2852 by Benjamin Fischer on 2016-05-09T13:30:24Z:

JSONData: implemented common interface to save (key,wsId) json data

this system is now used for storeing preferences (all of them)
closes #2327