* Remove inheritance of Citation from RefBase, using source_handle filed instead (similar to the way Family objects store mother and father handles) (also use the set_ and get_reference_handle functions more consistently)
* Use get_citation_list instead of get_citation_references (more consistent with the way notes are handled)
svn: r18100
* updates to citationviews to support all the functionality (add source etc.) provided by sourceview (including different tooltips for tree view and list view)
* moved registration of citationtreeview into view.grp.py
* removed citationtreeview.grp.py module
* fixed update to citation when note is deleted
* fixed update to citation when media object is deleted
* re-enabled edit button in sourcebackreflist
* improved date display in mergecitation
* changed default note type for citation notes
* changed backref in citation editor to CitationBackRefList
* fixed removal of citation handles from the list in primary objects when a citation is deleted
* fixes for pylint
svn: r18095
* Updated merge Sources
* Implemented undo-redo for citations (revision 18069 had only added citations to the undo-redo list, not acted on that types of element)
* Fixed embedded lists for some of the object type editors that were done in Rev 18069
* Modified EditCitation so the source parameter is optional
* Added svn properties for all /src/Merge/merge*.py modules
* Added support for EditCitation from backreflist.py
svn: r18085
Added Citations to undo-redo feature.
Moved Citation view within navigation pane to below Sources.
Removed useless edit button from sourcebackreflist.
Fixed default bottombar gramplets for citations.
svn: r18069
* Modified Event object to include references to Citations
* Implemented database upgrade for Events (upgrade for Media had already been done)
* Enhanced database upgrade to do backlinks
* Modified Media object to remove sourceref
* Implemented citations bottombar gramplet
* Some minor fixes and improvements
svn: r18054
* Changed database to introduce Citations
* Introduced new Citation Primary object and CitationBase (equivalent to CitationRef) child object
* Implemented CitationTreeModel and CitationListModel
* Implemented CitationTreeView and CitationListView for new citation views in the navigator
* Implemented EditCitation which is used both for the citation views in the navigator and for the citations of an object
* Implemented the CitationEmbedList to display the citations of an object
* Modified the bottom bar gramplets to support citations
* Implemented the citation selector.
* Modified Media object to include references to Citations
* Initial work on deleting citations
svn: r17960
