Include more info when collapsed requests remain in queue

[daveray]

When a collapser is shutdown and requests remain in the queue a warning message is logged. Include more details about the remaining requests (class, etc, etc) to assist in debugging.

[benjchristensen]

A new WARN message will be logged as:

"Request still in queue but not be executed due to RequestCollapser shutdown. Argument => " + request.getArgument() + " Request Object => " + request, new IllegalStateException()

[benjchristensen]

Merged into master.

I have one more small change I want to add before release 1.2.1 but will do so within the next couple hours so you can get this build into your environment for debugging.

[daveray]

This output was very helpful. I think I might have an idea what's going on now. Thanks!