4.0.5

1. Move the GeneratedDatabaseHolder off the last round, warnings should be gone!
2. Update Kotlin to 1.1.3-2
3. update Gradle plugin to 2.3.3 (3.0.0-beta currently breaks robolectric unit testing)
4. Some new extensions
5. add Property.allProperty(MyTable.class) so you can easily specify MyTable.* in a query.
6. Some optimizations on generated code including removing some redundant null checking.
7. Fix issue where DatabaseStatement in update were not closed when used in a ModelAdapter.saveAll() method.
8. Fix package private ModelView that duplicated field definitions in generated _ViewTable class.
9. RXJava2: Change Single to Maybe for nullable returns.