Remove manually setting `id` column name of test tables.

This ensures that the default value of `Id` is being set and working correctly.
Merge branch 'master' of github.com:pardom/ActiveAndroid
Merge branch 'master' of github.com:pardom/ActiveAndroid
Minor cleanup of tests.

Commenting and organized imports.
Fix test suite by setting a different database name for CacheTest.

This was causing an issue with the rest of the test suite, which was not passing because only CacheTestModel and CacheTestModel2 were in the database.
Merge pull request #205 from joshuapinter/fix_tests

Fix test suite.