Added $subname in the key of the DEPRECATED hash. Useful when calling several methods from the same line like when using the Bio::EnsEMBL::Test::TestUtils::test_getter_setter method.

Entire diagnostic execute function should be commented out.  Statement execution slightly slower otherwise.

* DBConnection now does a lazy connect (doesn't connect until first access to prepare, do, or db_handle methods).
* disconnect_if_idle can now be called by user processes and DBConnection will reconnect when needed.
* Reconnection is linked to db_handle method.  connect method will now only connect when needed.
* StatementHandle::DESTROY now calls DBConnection::disconnect_if_idle to disconnect so disconnect logic is consolidated in one place.
* New method ->connected : returns boolean as to connection state
* New Method ->disconnect_count : returns number of disconnect cycles DBConnection has gone through
* db_handle is now fork safe
* reduced number of db_handle->ping operations