Check the Modem Address on Startup

[krkeegan]

This will check the modem address on startup:
If no address is specified in the config file:

1. It will use the address obtained from the modem; OR
2. Fail and exit if no address is obtained.

If an address is specified in config:

1. If the returned address is the same, nothing
2. If the returned address is different, an error is reported,
   and things will continue using the address in the config.

Closes #266

• Works in testing
• Cleanup code documentation
• Change config.yaml
• Unit Tests

[krkeegan]

I also added the get_model functionality to the modem since we get that information with the address request anyways.

It could be useful for debugging or maybe something in the future.

[jonsmirl]

I don't know about this one...

If the returned address is different, an error is reported,
and things will continue using the address in the config.

I messed up my entire house network by having the sample modem address uncommented in the config and of course that didn't match my actual modem address. I had to repair every device again using the correct modem address. I would suggest exiting if they disagree with a message telling the user to fix it.

What would be a use case for wanting to use an address that didn't match your actual modem?

[krkeegan]

I am worried about messing up current installations that use the address configuration. The sample config file has been changed so that the default address is not enabled anymore.

[jonsmirl]

But why would you want it not to match the actual modem? If you write the links in with the wrong modem address like I did, nothing works.

Every LED on my switches was blinking red.