Promisify the right send.
Use single quotes.
Don't do the timeout in the write example.

This timeout was only there because of authentication not being required
for sending messages before.
Detect failure responses from RPC calls.

Now if the RPC call returns anything other than `SUCCESS` for its
result, it will fail the RPC promise.
Merge pull request #7 from nubs/master

Fix minor issues and detect failure messages from RPC (incl. auth)