[coretasks] Fix an issue with refresh_list which could cause it to forget all channel ops if the invoker was not a willie.admin

Also fix the docstring for list_voices
[coretasks] Don't try to handle NAMES if no channel was specified

This fixes issue #229
[core/ssl] Default to verifying SSL CN if SSL is enabled

Also, properly exit if SSL certificate verification failed
Merge branch 'master' of github.com:embolalia/willie