Copter: AC3.1.1-rc2 release notes
Copter: version to AC3.1.1-rc2

This update applies to pixhawk only
Copter: Update ReleaseNotes.txt
Add support for Porcupine Electronics LR4 + Fluke 414D, and set as default sonar rangefinder for ArduCopter
Don't set analog scaler if using UART