Add Quantum NEC OpenFlow plugin support

NEC OpenFlow plugin supports several OpenFlow controllers. This commit
also adds a third party script to support Trema Sliceable Switch,
one of open source OpenFlow controllers.

Change-Id: I5dddf04a25bc275c3119d751ca79b482e1875902
diff --git a/files/apts/trema b/files/apts/trema
new file mode 100644
index 0000000..e33ccd3
--- /dev/null
+++ b/files/apts/trema
@@ -0,0 +1,15 @@
+# Trema
+gcc
+make
+ruby1.8
+rubygems1.8
+ruby1.8-dev
+libpcap-dev
+libsqlite3-dev
+
+# Sliceable Switch
+sqlite3
+libdbi-perl
+libdbd-sqlite3-perl
+apache2
+libjson-perl