Fixes for queues being appended to the worker name and IDLE state workers.

A couple of potential fixes for setting the worker name and getting the worker state. 

The name of the worker was never appending the queue names to the end of the worker name because the name was set before queues had been populated in the WorkerImpl constructor. 

Jesque-Web was showing IDLE workers as WORKING in the Overview page. This applies a fix so that workers with no payload do not show up when asking for WORKING workers.