Add LPP payload generator

[donsez]

Adding a LPP payload generator with value taken into a value range could be a cool feature.

Values (including lattitude and longitude) could be generated with various functions (rand, sin, cos, linear ...)

This module could be imported for the payload encoding https://bitbucket.org/pni-jmattison/node-cayenne-lpp/src/master/

[kartben]

That's a great idea, @donsez! I've tried to stay away from implementing an actual simulation framework just yet, but maybe an option would be to use an external tool for generating CSVs of scenarios (using the kind of data generation functions that you are referring to), and then use this as an input for my tool? In a nutshell, I guess I would like to strongly decouple the traffic generation from the data generation aspect.

[donsez]

@kartben kartben Good remark. So the simulator can replay real LoRaWAN trafic extracted from logs with timestamp, payload, RSSI, LSNR, fCnt, DR ...