Rails needs to be loaded to meet all gem dependencies
No need to monkey with load path in gem, add to tests
Use ActiveSupport hooks to lazy-extend/include rails classes
Only ActiveSupport actually required, not Rails gem
Update test schema.rb to match current migration

However, set force: true and didn't set indices

Fixes test failures for postgresql::

No integer type has byte size 11. Use a numeric with precision 0
instead.

https://travis-ci.org/mbleigh/acts-as-taggable-on/jobs/15196579

see https://github.com/rails/rails/issues/6272
Add .travis.yml bundle cache
Use #detect in Rails to avoid conflicts with AR.find

Fixes

https://travis-ci.org/mbleigh/acts-as-taggable-on/jobs/15206376
Refactoring; Ensure queried tag is 8bit ASCII

Fixes SQLITE3 failures
Merge pull request #430 from bf4/fix_build

Fix build