Translation-BR

#### Issue details
linking ardupilot_wiki issue that better belongs here
https://github.com/ArduPilot/ardupilot_wiki/issues/657
#### Version
n/a

#### Platform
[ x ] All
[ ] AntennaTracker
[ ] Copter
[ ] Plane
[ ] Rover
[ ] Sub

#### Airframe type
n/a

#### Hardware type
n/a

#### Logs
n/a

Start with the linked ArduPilot/ardupilot_wiki issue #657, since this issue says the work belongs there. Confirm the requested Brazilian Portuguese translation and its target documentation, then use that issue's stated scope to determine what completion means; no Mission Planner file or test is identified here.

Written by the indexing model from the issue text.