Enhancement: Consider other database persistence libraries as an alternative to Sugar ORM.

[huhx0015]

While Sugar ORM is simple and easy to use for data persistence, it may be too basic when storing more complicated data in the future. Also, the current release of Sugar ORM is currently incompatible with Android Studio's Instant Run feature; a fix has been merged, but no word on when the next version of Sugar ORM will be released: chennaione/sugar#564

Other database persistence libraries like Realm, DBFlow, Room, GreenDAO, etc. should be considered as possible alternatives.

Reference: Performance Comparison of Database Libraries by Andrew Grozner: https://github.com/agrosner/AndroidDatabaseLibraryComparison2/tree/master/app/src/main/java/com/grosner/androiddatabaselibrarycomparison2