Bug 183249

Description of problem:
The current code base has a pretty backwards way of dealing with different
versions of Bugzilla. Basically it boils down to the fact that you need a
separate class hirarchy (thankfully consisting of only 2 or 3 classes) for each
new version. The problem is that there is pretty much no change between some
versions, and then only thing that needs to be changed is checking that the
correct version is used. This needs to be cleared up by either changing the way
the version is detected and the way the BugzillaFactory works, or by making a
class that is not version specific but is something like 18+ or 18_and_up.

Version-Release number of selected component (if applicable):
0.2.2