Keep header comment on minify

Some minifier keep header comment over its format.

1. YUI Compressor
It keeps the header comments beggining with `/*!`
  * http://yui.github.io/yuicompressor/css.html#special-comments

2. Closure compiler
It keeps the header comments containing `@license` or `@preserve`
  * https://developers.google.com/closure/compiler/docs/js-for-compiler#tag-license

I think header comment is very important because it includes its own license.
Do not depend star
Delete trailing spaces
.commit handles errors properly now
use options.user (options.username is undefined)
Test verifies `.commit()` error handling
Use authenticated name and email when committing

fix #128
npm run lint now passes
Travis now runs jshint

Ditching old node versions because test libs don't work well with them
typo Git → Gist
Merge pull request #134 from codingisacopingstrategy/patch-1

typo in README; Git → Gist
Merge pull request #132 from iamdanfox/jshint

JSHint
Merge pull request #116 from Raynos/patch-1

Do not depend star
Switch to Tape
Bump Version
Merge pull request #138 from michael/tape

Switch to Tape
Merge pull request #95 from tricknotes/keep-license-on-minify

Keep header comment on minify
Regress package number in github.js
Shared user file
user tests