necsis14: Working on the transformation example (2)

 * A lot of necessary engine and query changes to properly handle
example queries
necsis14: Working on the transformation example (3)

 * Fix wrong line index in _exColumns query
necsis14: Working on the transformation example (4)

 * Fix Database metamodel
 * Add proper non-containment EReference treatment (derivation +
transformation)
 * Review EAttributes
necsis14: Remove unnecessary checks, leave todos
misc: Add relative uri option to open gmf diagram api
OpenGMFDiagram
Merge branch 'master' of https://github.com/adisandro/MMINT into highlighting
code review changes