-Revamp Table.pm to share database handles and have handles persist across object instances, avoiding numerous calls to connect in certain programmer use cases.
-Modify xfork to use the aforementioned structure rather than the generic structures which are warned as being read-only
-Remove probably deprecated interface field as a key in mac table
git-svn-id: https://svn.code.sf.net/p/xcat/code/xcat-core/trunk@317 8638fb3e-16cb-4fca-ae20-7b5d299a9bcd
