Add build.js to test directory.

This commit adds a build.js file compiled by Component to the test
directory so that users can test postpone without needing to install
Component or build a sample app with Browserify.
Enhance postpone with UMD pattern.

This commit enhances postpone with a Universal Module Definition
pattern. Employing this pattern means that postpone can now be used
easily in none CJS-style environments and can be used as a stand-alone
module as a browser global.

This commit also removes the `docs` directory; the code is thoroughly
documented and interested users can generate docs for it using jsdoc
and similar tools.
Bump versions.
Bump versions.
Automatically rewritten for npm.