(Issue #54) Added weight is broken.

Changing golem behavior process to only run when there were idling
golems broke the workflow for added weight. Normally, it would check if
behaviorScores was empty (something only possible if the idling golem
list was empty or the task queue was empty). Since the golem list would
always be greater than zero, this became dead code. The check has been
moved into execute() in GolemBehaviorProcess, and runs if there are no
available golems.