fix issue #242
Add a .gitattributes file to avoid merge pbs with metadata.
Merge remote-tracking branch 'dale/master'
Adds MetacelloPlatform>>tempFileFor:suffix:
Removes MetacelloPharo30Platform>>tempFileFor:suffix:
Merge remote-tracking branch 'dale/master'
Merge pull request #256 from demarey/master

fix issue #242