preparation for turning off Dataflow Optimizer to speed up optimized compiles (at optimization levels less than 9)

* splits -XdisableAggressiveOptimization into five more granular flags
* marks -XdisableAggressiveOptimization deprecated
* cleans up inconsistency in existing Options and ArgHandler implementations

Change-Id: I2f33700566e97672b2e570fc5f75293bd6b2fb9f
Review-Link: https://gwt-review.googlesource.com/#/c/2610/

Review by: rluble@google.com
Added missing compiler options to JUnitShell.

Added JUnitShellTest to JUnitSuite.

Change-Id: I5a4c3747bedaf5db84b0c7ffefdd83da64d060d7
Review-Link: https://gwt-review.googlesource.com/#/c/2611/