Updating Buck files to build OSGi jars

- Using osgi_jar for all modules except apps
- Adding target for installation of core modules to .m2 repo

Change-Id: I65d9e3a9567918e275191724842d7d9b1f485128
diff --git a/providers/openflow/message/BUCK b/providers/openflow/message/BUCK
index 721518c..dff2a84 100644
--- a/providers/openflow/message/BUCK
+++ b/providers/openflow/message/BUCK
@@ -15,7 +15,7 @@
     '//lib:TEST',
 ]
 
-java_library(
+osgi_jar(
     name = CURRENT_NAME,
     srcs = glob([SRC + '/*.java']),
     deps = COMPILE_DEPS,