[MIE-1608] Added a simple pagination service and implemented it in every endpoint returning lists. 

Pagination Service receives a query object, like: {'offset': 1, 'limit': 50} and a list of items, and return a subset of that list representing the requested page. Default is set to  {'offset': 1, 'limit': 50}

Implemented Pagination Service in every endpoint returning lists. Example: if you go to */api/v1/object/db_user/1/activities* , you can add the query **?limit=20&offset=1** to the URL to filter your results.

Unit tests and bateries provided!
These tests are good so far. Can you add some more tests that use an array of items instead of a hash to test that logic?