Offline methods and updated dependencies

Hello everyone,

after talk with some people that is already using the library we saw that when using methods such as get, set, update that should work when the device is offline, the Rx calls(onComplete, OnSuccess) were not called because the tasks never call onSuccess until the data is correctly uploaded to the server.

To make this more easy to work with, new methods called setDocumentOffline, updateDocumentOffline, addDocumentOffline anddeleteDocumentOffline have been added to the library. All of them will execute their respective calls without wait for the Task to be completed.

Thank you so much for the support !