Provide an improved heap summary for G1GC with parameters like 'capacity', 'used', 'free', etc with the 'universe' command, and introduce a new command 'g1regiondetails' to display the individual region details. Reviewed-by: sjohanss, minqi
SA Test cases for the clhsdb commands: universe, intconstant, type Reviewed-by: dholmes, sballal