Minimed glucose support

[loudnate]

Insert glucose data from sentry packets if it exists.

[loudnate]

Depends on #10, which will auto-configure timer tick based on absence of the G5 hearbeat.

[loudnate]

Hmm, I thought this is what @oskarpearson needed, but it turns out he needs to poll glucose pages. This should be paused until someone comes along who needs and can validate this configuration.