Make `GifWriter` class; currently it only can write GIF header
Write `writeLogicalScreenInfo` method
Write `writeTableBasedImage` method
`writeTrailer` method
Merge: Fundamental features of GIF encoder
Graphic Control Extension and Image Position
Test of `writeTableBasedImageWithGraphicControl` method
`writeLoopControlInfo` method
Merge: Features for animation GIF
Add “.travis.yml” file
Move common code for test to “test/test_common.ts” file
Add `MedianCutColorReducer` class
Fix Jakefile
Merge: `MedianCutColorReducer` class
Update README file and add LICENSE file
Version 0.1.0