Removed uppercase from name of package as npm will not allow publishing ...

...uppercase packages, better description.

I've published this package to `npm` but I'd be more than happy to delete it when the Polymer team wish to publish to `npm`. One note about publishing to `npm` some of your packages have upper case names/directory names which aren't allowed in `npm` and therefore the `script` tag that are written to the document to load other parts of the polyfills will no longer work so when things are published to `npm` package names will all have to be lower cased.