Distributed Scheduling has invalid AMRMToken

There are two problems in enabling distributed scheduling.

1. If we enable the distributed scheduling only, the amrmproxy will start automatically and replace the token with the local one for apps in order to proxy any communication with rm. However, the am will still send its register request and allocate requests directly to real rm, and thus has invalid token.

2. If we enable both of these two settings, we would have invalid token too. And I don't know why.