Description of problem:
The kernel team is trying various tricks to link 5.1 bugzillas to a 5.0.z
bugzillas.  The idea is to prioritize 5.1 bugzillas that have an associated
z-stream bugzilla higher than normal ones.  We want to prevent patches from
being checked into the z-stream before the 5.1 branch.

In order for me to filter for this information, we decided to add 5.0.z to the
'devel whiteboard' block in bugzilla.  Using the XMLRPC function like
getBugSimple() I can grep for 'devel whiteboard' and if it is populated move
that bugzilla higher on my queue.  

Unfortunately, getBugSimple() does not provide the 'devel whiteboard' info (yes
getBug() does, but that seems too heavy).  Unless the bugzilla team has a better
hack to resolve our problem, I would like to request adding the 'devel
whiteboard' info to getBugSimple().