Added request counter to Paginator

Added instrumentation for Paginator so API clients can understand the number of requests executed per search.
Sorry I didn't response earlier, Elmer.

I just committed some code to utils-java that solves this for you. There is a new subtype of Genomics called RequestCountingGenomics, that has two methods initializedRequestsCount() and unsuccessfulRequestsCount() in addition to the normal stuff you expect on the Genomics API stub. The maven release is happening as we speak - the version is v1beta2-0.9

So, I think this PR is obsolete now.