Automate extracting PNG images from "Apple Color Emoji.ttf"
Extract and optimize PNGs from "Apple Color Emoji.ttf"

Commands used:

    $ rake images:extract
    $ imageOptim -a -d images/emoji/unicode/

This required both ImageOptim and ImageAlpha to be installed as OS X apps.
Update test for expected identical emoji checksums
Simplify special case for "black_medium_square" in checksum test
Run the rest of the PNGs through ImageOptim

Command used:

    $ imageOptim -a -d images/emoji/
Tweak extractor.rb code style
Merge pull request #63 from github/extractor

Extract PNG images from Apple's "Apple Color Emoji.ttf" font
Test against Ruby 2.2 on Travis CI
Merge pull request #65 from tricknotes/ruby-2.2

Test against Ruby 2.2 on Travis CI
Add emoji for :basecamp: and :basecampy:
Add :basecamp: and :basecampy: to emoji.json
Merge pull request #66 from asianmack/basecamp

Add emoji for :basecamp: and :basecampy: