copy proto to distribute directory

Author: junshi15

Makefile

@@ -651,6 +651,8 @@ superclean: clean supercleanfiles
 $(DIST_ALIASES): $(DISTRIBUTE_DIR)
 
 $(DISTRIBUTE_DIR): all py | $(DISTRIBUTE_SUBDIRS)
+	# add proto
+	cp -r src/caffe/proto $(DISTRIBUTE_DIR)/
 	# add include
 	cp -r include $(DISTRIBUTE_DIR)/
 	mkdir -p $(DISTRIBUTE_DIR)/include/caffe/proto