newest version - _0_13
- changed communication to device to initiate protocol from a number from 000 - 999, to a full JSON containing all of the necessary information for the protocol to run
- In new JSON comm protocol --
   - all environmental variables can be called either before or after the main spectroscopic measurement using the 'environmental' nested array
   - uses ArduinoJsonParser library
   - multiple protocols may be presented in the format [{<protocoljsonhere>},{...},{...}...]
   - each protocol may repeat itself using the 'repeat' variable
   - each set of protocols may repeat itself using the 'measurement_groups' variable
   - a user can set a delay between measurement groups using the 'measurement_groups_delay' variable
   - now measurement lights and detectors can be changed on the fly (for each analog_read) throughout the measurement
   - example JSONs for fluorescence, ECS, etc. are available at the top of the the file
- now using htu21d library instead of manually performing calls
- add option to switch back and forth between new detector setup (with integrating cap) and old detector (will be phased on out next push hopefully) - NEWDET and OLDDET

further improvements / changes -
   - using lots of memory by keeping all of the parsed JSON and saved results from it in memory - needs cleaning up
   - more code cleaning, pull variables out of global to local, convert more variables to constants
   - more work on calibrations for the sensors
   - add error codes
   - define exactly the limits to number of protocols (about 12 or 13 now), and number of measurement lights (if any)... size of overall incoming communication JSON... etc.

Signed-off-by:  <Greg>