Added Hobbywing ESC telemetry (DO NOT MERGE)#106

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tridge wants to merge 10 commits intomttr-rebase-3.6.7from

pr-hobbywing-esc-telem

Commits on Feb 14, 2020

AP_ESC_Telem: fixed current reporting
tridge
committed

Commits on Feb 20, 2020

Removed un-needed pre-arm checks for this configuration
Aksellence
committed

Commits on Mar 9, 2020

AP_ESC_Telem: fixed scaling of RPM
tridge
committed

Commits on Apr 1, 2020

AP_ESC_Telem: update based on new protocol docs
tridge
committed

Commits on Apr 17, 2020

DataFlash: DISABLE persist logging for 60s after disarm or arming failure
Aksellence
committed