quote args passed through SSH in SSHLaunchers

they need double-quoting for some reason, when passing through SSH.

IPython/parallel/apps/launcher.py

@@ -584,7 +584,7 b' class SSHLauncher(LocalProcessLauncher):'
 
     def find_args(self):
         return self.ssh_cmd + self.ssh_args + [self.location] + \
-               self.program + self.program_args
+               list(map(pipes.quote, self.program + self.program_args))
     
     def _send_file(self, local, remote):
         """send a single file"""