Add parameter to point to hbase-site.xml

[hildrum]

Add a parameter to specify an hbase-site.xml.

• if hbaseSite parameter is used, that file will be used.
• if no hbaseSite parameter, the operator will expect to find hbase-site.xml under either HBASE_HOME/conf or opt/downloaded.

One problem is that I cannot make the setting of HBASE_HOME optional. If I include it in the operator model, the compile will fail if it's unset. If I don't include it in the operator model, then I cannot access it at runtime.