Supporting Limit, Offset in Queries
Misc Updates

* Updating Sort to support ascending and descending sort
* Fixing small bug in Commit handling for commit ids
* Fixing bug in Text handling for String fields in HTTP
Remove PointerCalculatorFactory

* clean up pointer calculator tests
* move construction of shared_ptr into static PointerCalculator::create
Cleanup pointercalculator class, added override spec
Merge pull request #155 from bastih/feature/remove_pointercalc_factory

PointerCalculator cleanup