Update dependencies

Update (jahirfiquitiva#25)

* Update to Android Gradle Plugin 3.0.0.
* Update libraries.
* Reformat code.
* Update .travis.yml
* Remove unnecessary classes

Fixes and code organization (jahirfiquitiva#23)

- Organized project structure
- Update code style
- Fixed a couple things here and there

Minor fix

Minor change

Minor code cleanup

Test crash fix

Code cleanup

Update [ci skip]

Code cleanup. Udpate licenses notices