Remove license comment duplication

`*.min.js` already contain license comment because uglifier keeps
license comment that marked up with `@license` tag.

This duplication is injected in #3865.
Include version to header comment

It is useful that version is kept after minify.
bundle update

To follow up emberjs/ember-dev#116 .
Merge pull request #3996 from tricknotes/include-version-to-header-comment

Include version to header comment
small computed docs fixes
Merge pull request #3997 from twokul/computed-doc-fixes

small computed docs fixes