Adding ability to read/write Permission Configs and cli to access them

- Added the ability to set/list/remove permission configurations from prefixes.
- Most of this was a mimic of what Spencer wrote for the zone configurations.
- Also consolidated some of the repeated code where I could.

Once this is merged, I'll create a similar treatment for Accounting Configurations.
You could always rename the protos as well. Getting the right name is important and will only get more difficult to change from here out. Spencer?