Move resource discovery to common jax-rs service

Change-Id: I9e684a85e61a4692d77356a4889a0883f0fed967
Reviewed-on: https://pirx.atteo.com/gerrit/588
Tested-by: Mr. Jenkins
Reviewed-by: Sławek Piotrowski <sentinel@atteo.com>
Load test-config.xml only when @MoonshineConfiguration was missing

Change-Id: Id5fba8e6aff67d564bd24dfd89b767bc3a712935
Reviewed-on: https://pirx.atteo.com/gerrit/589
Tested-by: Mr. Jenkins
Reviewed-by: Sławek Piotrowski <sentinel@atteo.com>