GEOMESA-120 Extract Temporal Filters

* We now extract the temporal range to cover from the applicable temporal filters.
* Since FilterToAccumulo is no longer used, it has been deleted.
(This required tweaking one unit test.  Additional clean-up was involved.)
* Added 'pendingUntilFixed' unit tests to the QueryStrategyDeciderTest to reflect further work.
[ignorable rant]  It would be really useful if we were to document -- in one place -- all of our assumptions about what we will (not) accept in `Filter` children.