Structural changes.  Includes removal of RHIPE as well as combining parallel renderers, introducing 'selector' interface and misc test updates.
Draft subset-boundless.
Removed caching from memmaplist subset.
HARD TO BELIEVE GOOD performance by rebalancing task size....
Removed 'task size' controling parameters.
Further structural changes for 'Selectors'
Selector lifted out.
WIP: Merge Selectors with aggregate-without-bounds, failing some key tests still.
Removed 'intersects' from glyphset; re-implmeneted serial to use Selectors.
Changed default window size.
Relabling and a correcting some documentation.