FTP: Better timeout handling

Onboard Files fixes

Debounce misconfiguration, fix onboard files view

FTP Unit Test fix

Mavlink File Transfer Protocol (FTP)

Changed FTP to tree view

Also added selection from tree view for downloading

FGFS multicopter HIL

Mavlink FTP: List and Download commands working end to end

Google Maps fix

Fixes to botched Qwt 6.1 update

Also modified protocol to better support eof’s on list and read
commands.

Update Qwt to 6.1

Fix linux release build warning