Resolving the dependency to GMF Tooling

Many thanks to Alessio Di Sandro <adisandro@xxxxxxxxxxxxxx> for
providing the patch this commit is based on.

https://www.eclipse.org/lists/henshin-dev/msg01252.html

Change-Id: Id41e42f9ec61afb7bbd12ab2419d2f878e134630
53 files changed