Issue #105_kkallas - Rework of Backend/Frontend telemetry processing

[Futabay]

• Updated dict.iteritems to dict.items (Update dict.iteritems() (Py2) to dict.items() (Py3) #169)
• Added dntoeu plot option
• Added getPacket utility method

[MJJoyce]

Noticed when testing a bit that it doesn't look like Derived values are making it to the frontend / working at the moment.

  derivations:
    - !Derivation 
      name: Volt_Diff
      desc: Difference between Voltage_A and Voltage_B
      equation: Difference(Voltage_A, Voltage_B)
      units: Volts
      type: MSB_U16

That's in our default tlm.yaml. If I add that as a field I'm not seeing anything get displayed for it. We'll have to dig into the code creating a clean diff and see if those are getting picked up. I'm fine with handling that in a follow up ticket though.

[Futabay]

I will investigate that. Would you mind creating the following up ticket?

[MJJoyce]

Not that the logic below is wrong, but couldn't we simplify a bit?

// Default to the raw value since it will always be avilable
let value = data['raw']

// If raw==false and a DN to EU value exists, grab that
if (!raw && data['dntoeu']) {
    value = data['dntoeu']
}

return value

[MJJoyce]

👍 Merging as is. We can open follow up tickets as needed. Thanks for getting it integrated!