DSE History refactoring
Fixing of DSE history and adding new functionality.
- user can trigger save of current history
- when new TAs are generated, a new history object is generated
- when new deployments are generated the user can decide to override existing deployments or to create new history element (including newly generated deployments)
(from redmine: issue id 2307, created on 2015-03-09, closed on 2015-08-14)