Reporting API Framework

Details the beginnings of a Report API framework.

ConsumerStatusReport will get another rev after this is merged in and currently returns static data.

Please focus how reports will be created. Need to make sure this is pretty straight forward and relatively easy to do.

NEED TO BE DONE, NOT IN THIS COMMIT
* Exceptions and mappers need to be merged into candlepin-common so that they can be reused here.
* Currently ReportParameters are purely for providing parameter info when requesting report details -- It would be nice for them to contain validation code for each so that we wouldn't need to implement a validation method.
ArrayLists are great for random reads, not so great for appending.  I think by deafult it allocates a length 10 array, then reallocates and copies all the data when the limit is hit.  Feels like a LinkedList would work better since we only ever iterate over it, right?

Practically though, I'm not sure if the difference is measurable.