Add unminified 'amd-shim' to tools

Unminify the amd-shim and move it to the 'tools' directory.

Will be moving all the standalone-generating stuff out of 'lib' to keep
that focused on Flight's library code.
Add version/license banner template

The template for the version/license banner comment that will be at the
start of the source and minified standalone flight.js.
Add script to generate standalone flight bundles

Extension of the existing build script, with the following changes:

* Create both a minified and unminified version of flight.js.
* Add the version and license banner at the start of both files.
* Use uglify.js to fully minify the combined shim + lib code.

N.B. The creation of an accurate banner is dependent on the
`package.json` version number being kept up to date.
Update Makefile tasks to build standalone

Create a 'release' directory to house all the released versions of
Flight.

* Each new version of flight will have its unminified and minified
  variants added to the 'release/{{version}}' directory.

* Historical archive of previous versions will be retained.

* Latest published version will always be available in 'release/latest'.
Remove previous shim and build files

These have moved to the 'tools/standalone' directory and been updated.
Update Bower ignores

Reflect the change of directory for the build tools.
Merge pull request #120 from twitter/feature/standalone-flight-banners

Update standalone flight.js build products