8186248: Allow more flexibility in selecting Heap % of available RAM
Reviewed-by: dholmes, drwhite

8180600: make run-test does not work with jib test dependencies
Reviewed-by: ctornqvi, ihse

8180281: --with-jtreg is broken for many use cases
Reviewed-by: erikj

8177955: Add testing documentation
Reviewed-by: erikj

8176084: Developer-friendly run-test facility
Reviewed-by: erikj