Refactor crop logic (again)
Slightly refactor enlarging logic, and add enlarging option to the rest of the size manipulation methods
Make source image type property public
Add initial PHPUnit unit tests and Travic CI config
- more tests still need to be added to make this a good safety net
- the testOutput* methods probably need to be refactored
Bump composer version
Merge pull request #8 from cainmi/master

Unit tests, refactored cropping