MetricsServiceProducer should not log "Using a backend implementation of null"
when backend implementation is chosen by default.
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
Let the developer configure desired logging with system properties

Now by default, Wildfly logs at ERROR level in the CONSOLE and DEBUG level in
the project.build.directory/test.log file.

For this to happen, we need to copy a the /src/test/wildfly-resources file (filtered)
to the Wildfly standalone configuration directory during the process-test-classes phase.

Example:
mvn verify -Dwildfly.logging.console.level=DEBUG

Also:
* removed useless <id>Memory-backend</id> profile definition (it is the default)
* removed redundant info in Cassandra-backend profile