MsgFlo participants on coordinator unable to subscribe due to permissions

[jonnor]

Because they attempt to subscribe to topics on form myparticipant.PORT, which is currently not allowed to read/write from in our mosquitto config. In general only /public/* is open for R/W...

So either all participants must obey a prefix (msgflo/msgflo-nodejs#11 and same in msgflo-python, etc), or we change this configuration to make most things open. This should be fine as long as we ensure that our security sensitive topics. A test-suite that ensures this would be probably be the best anyways.

While debugging found that there are no error for subscription failures:
msgflo/msgflo-nodejs#10

[jonnor]

Wrote tests for our access lists, in https://github.com/bitraf/bitraf-iot/blob/master/test/access.coffee
and then found that allowing readwrite + in mosquitto did not break the stricter permissions on /bitraf/door/+/open. CC @trygvis