Make the scripts generic. Adds an option that allows you specify
'project'. Defaults to 'hbase' for core. Pass 'hbase-thirdparty'
or 'hbase-operator-tools' etc.
This commit includes a bunch of bugfixes and miscellaneous
that came of trying to use the scripts making RCs.
Signed-off-by: Peter Somogyi <psomogyi@apache.org>