Deploy across an entire web cluster

Adds deploy, undeploy, and redeployAll to webapp cluster entities (DWAC and ControlledDWAC).

Also fixes some issues noticed in how tasks are tracked and displayed.
why `static`? I'd go for `private final`, even though it could be static given it is stateless. No reason to make it a constant that I can see. If it is left as a constant, the variable name should be in capital letters.