Removes dao factories

Dao factories are not required anymore. Instantiation will be handled by
dagger's injection framework.
Adds base content provider and dao classes

Base content provider class will handle injection in its
ContentProvider.onCreate() method. Application class had to be updated
to instatiate the object graph properly.
Adds sqlite content provider

Added generic content provider to handle request from clients. Content
uris must contain the sql table name only to operate on. The request
will then be translated into an sql statement and executed.