Allow API consumer to search by groups

[jmiranda]

To search the backend group, the following set of query string parameters will be needed. The " group" is an array of elements with the identity of the groups (if more than one group id is defined then the search will be using the AND condition). Here is a sample of query string (see image below):

The results should be a list of the annotations.
FYI: The group creation is done separately all you will be storing is the group id from our group database.