App versioning update.

[UPDATED]   App versioning: version is now: decimal short commit hash, short version is now tag+commit number.
Don't use temporary objectIDs for state.

[FIXED]     Make sure we have permanent ObjectIDs before storing them in state.
[FIXED]     MP-14
Avoid using object.managedObjectContext - when no strong reference exists to the MOC, it may yield nil.

[FIXED]     Unexpected nil MOCs.