jhat: update parser to read JAVA PROFILE 1.0.2 dumps

The CCC 6305542 details the update to the HPROF binary format to support large multi-GB heaps. jhat's parser needs to be updated to read these dumps

Note that this RFE is submitted to cover the updating of the parser only - there is a longer task need to update jhat so that it doesn't need to read the entire dump into memory.