Modification for Ubuntu 13.10 and minor fixes in Neutron NEC plugin

Modifications for Ubuntu 13.10:
* Add .conf suffix to apache2 config files. In Ubuntu 13.10,
  files in sites-available should have ".conf" suffix.
  Otherwise it is not recognized by a2ensite.
* libglib2.0-dev is added to lib/files/apt/trema. Trema is
  an OpenFlow controler framework used by Neutron NEC plugin
  Ubuntu package dependency seems to be changed.

Minor cleanups are also done in OVS configuration:
* Set datapath_id before connecting to the OpenFlow controller
  to ensure datapath_id changes after connected.
  Previously datapath_id is changed after connecting to the controller.
* Drop "0x" prefix from datapath_id passed to OVS.
  OVS ignores datapath_id with 0x prefix.
* Fix a bug that SKIP_OVS_BRIDGE_SETUP skips all confiugration of
  the plugin agent. It should skip only OVS setup.

Change-Id: Ifac3def8decda577b5740c82fe8d24e8520c7777
diff --git a/lib/neutron_thirdparty/trema b/lib/neutron_thirdparty/trema
index 5b5c459..9efd3f6 100644
--- a/lib/neutron_thirdparty/trema
+++ b/lib/neutron_thirdparty/trema
@@ -28,7 +28,7 @@
 TREMA_LOG_LEVEL=${TREMA_LOG_LEVEL:-info}
 
 TREMA_SS_CONFIG=$TREMA_SS_ETC_DIR/sliceable.conf
-TREMA_SS_APACHE_CONFIG=/etc/apache2/sites-available/sliceable_switch
+TREMA_SS_APACHE_CONFIG=/etc/apache2/sites-available/sliceable_switch.conf
 
 # configure_trema - Set config files, create data dirs, etc
 function configure_trema() {