Restrict scale on state comparison

[byronwall]

It'd be nice if the comparative plot was limited to a maximum y axis value of 3 (similar to the other R plots). Guam has been throwing things off for the last several updates:

[jhellewell14]

Hello, thanks for flagging this. It looks like Guam has got slightly better over time and is no longer causing this. However, there does seem to be a general issue that reproduction number estimates are generally wider in places with fewer reported cases (even if this is as a result of their epidemic slowing down). We're going to be moving to a new model for estimating the reproduction number soon that we hope will iron out this problem (EpiNow2).

Cheers,
Joel