Fix for parasite powered devices (lose 5V line). These showed up in detected devices, but are unable to perform temperature conversions.
This fix hides them in the device list.
added switch case to check that device is a temp sensor before initializing it as one
Fixed missing else (if instead of else if) in detectPeaks, alerted by MC1 on the forum.
Lumped in with hotfix to merge into master, because it is a minor change that was higly unlikely to cause issues.
Merge branch 'hotfix/0.2.4.2'