wednesday updates

1. verify/fix all 'set name' operations
2. (modestly) optimize device.{get,set}Name()
3.  have yoctopuce voc report both ppm and sigmas (for now)
4. catch mdns createBrowser exception
5. update to sandeep's lastest BLE packages
6. tell console.html about voc
7. deviceType typo in drilldown.js