Migrating EDM to atlas/athena master and to build directly against it.

All EDM changes migrated to the new build strategy. That means the creation of new packages based in ATLAS code (e.g. xAODFaserTruth). To avoid conflicts when building against the full ATLAS athena release, these were always renamed with "Faser" in the name. This also applies to the underlying classes. This way it is obvious for developers that these are somehow relics from ATLAS code and not completely new classes/packages. Packages which can be used directly from the ATLAS build habe been removed from the project. This builds as described in README.md - same way as the original project by Dave.

@dcasper, please have a look and merge this when you are happy. Please also merge in your latest developments now that the master branch seems to be "fixed".