Merge tag '0.7.0' into develop

0.7.0
Add gittip badge.
Add MacOSX to CI environment.
Merge branch 'develop' of github.com:yasuhito/text2048 into develop
Add author section.
Add LCD class to display numbers nicely.
Larger numbers.
Refactor.
Fix scaling.
Merge pull request #4 from yasuhito/feature/lcd

Feature/lcd
Version bump.
Merge branch 'release/0.8.0'