Create plugin for coref editor
Add .corefeditor to parent POM
Add editors extension point
Update plugin.xml
Create basic classes for coref editor
Add coref editor plugin to run config
Implement show document text
Implement handler, property tester and keybinding for creation of
markables
Implement text editor part of coref editor
Create "Create reference" handler and refactor to use abstract
superclass
Prepare refactoring
Refactor for new reference handler to use new markable handler, not
fully-implementing abstract superclass
Add DND support for Reference View
Programatically set text dnd support in IPreferenceStore to true
Refactor GraphResolver into new .editors plugin
Implement full drag'n'drop for ReferenceView
Fix text display in Reference View
Fix display order of markables in Referent Tree
Implement ReferenceEditor with SashForm to take in text view
Implement SourceViewer on new Coref Editor