Extend JIRA's system-webresources-plugin to offer all framework components

We should extend the system-webresources-plugin.xml so that it contains all of the various files that make up our component frameworks: Prototype, Scriptaculous, DWR and YUI. They should be individually addressable so that a plugin author can request just the ones he needs.

Secondly, we should really be using the *-min and combined versions of these files, as you can save 50% or more download time.