Allow setting owner, description, clone/push url metadata in the project array

This adds four new keys to the project array metadata:
'owner': overrides the owner of the project
'description': overrides the description of the project
'cloneurl': overrides the clone url of the project, can be an empty
string to explicitly remove the clone url
'pushurl': overrides the push url of the project, can be an empty string
to explicitly remove the push url