Slim down UI Console WAR

From 43MB to 8MB

The proper way to exclude webapp resources when copying them to
the target directory is to use the 'warSourceExcludes' tag

Besides, now all resources useless at runtime are listed.

Also, don't pollute the WEB-INF directory with an empty classes directory.
Merge pull request #60 from tsegismont/slimDownConsoleWar

Slim down UI Console WAR
Merge branch 'master' of https://github.com/rhq-project/rhq-metrics