filenames with spaces.
- Added new Util.rawEncode which encodes the right set of characters (based on
  RFC1738) and deprecated Util.encode which only encodes non-ASCII.  Unit test too.
- Change previous fix to use Util.rawEncode instead of URLEncoder.encode
- New fix: add h.xmlEscape call for each displayed filename in artifacts/workspace
  so & and < are encoded for HTML display
- Add all these fixes in Run/artifacts-index.jelly which wasn't included before


git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@14355 71c3de6d-444a-0410-be80-ed276b4c234a