Enhance JBossLauncher and remove unnecessary classes.

Switch JBossLauncher to ModelControllerClient interface (allows better
error messaging).

Remove CLI class (was used for manual testing during development, but no longer
necessary).

Improve method of starting Jboss AS instance: attempt to connect to it
every second until success or a maximum number of attempts is reached.
Fix error message when empty string is given for errai.jboss.home property
Add errai-client-local-class-hider and jboss-as-dist as dependencies.

This way they are pulled in transitively for users.