add --recursive flag for submodules

comp.py

@@ -29,7 +29,7 @@ class GitRepo(Repo):
             print('INFO: branch %s does not exist on %s' % (branch, self.url))
             branch = 'master'            
             print('INFO: checking out %s' % branch)
-        cmd = "git clone --branch %s %s --quiet %s %s" % \
+        cmd = "git clone --recursive --branch %s %s --quiet %s %s" % \
             (branch, depth, 
             self.url, self.name)
         return cmd