hawtio v2 - concise and consistent naming for logging categories

Logging categories are inconsistent in hawtio v2 (see the image). We need to have a consistent one.

My idea is that for a plugin named hawtio-[name] the primary log category be [name], e.g. the log category of hawtio-jmx be jmx. If the plugin has sub categories, it should be [name]-sub1, [name]-sub2, [name]-sub3... e.g. jmx-workspace.