Change DeploymentRootMountProcessor To Use Marker to Determine Whether to Mount Exploded

Right now DeploymentRootMountProcessor is hard-coded to only mount .war files exploded. For TorqueBox, we have the need to mount .knob files exploded. It would be great if there was some ExplodedRootMarker that DeploymentRootMountProcessor checked instead of looking at the file extension. This would mean moving Phase.STRUCTURE_MOUNT to some value greater than 0 to allow an earlier processor to call ExplodedRootMarker.mark(...) for .war files and let TorqueBox create its own processor to do the same for .knob files.