Fork throws exception on success

[Spenhouet]

If the forkProject operation was successful an "201: Created" exception is thrown.
Throwing an exception on a successful operation is a strange behaviour.

This should not happen. Only throw an exception if an error occurs.

[gmessner]

There was a bug, forkProject() was looking for HTTP status 200, not 201. This has been fixed and is available in release 4.7.2