Update readme and license #3597

Job	Run time
coverage (ubuntu-20.04)	4m 47s
ubuntu-20.04 (mavsdk, hunter)	3m 49s
ubuntu-20.04 (non-mavsdk_server, non-superbuild)	5m 4s
ubuntu-20.04 (mavsdk_server, superbuild)	11m 22s
ubuntu-22.04 (mavsdk_server, superbuild)	10m 4s
alpine 3.16.0 (musl)	15m 15s
Ubuntu/Debian packaging (Ubuntu 20.04)	5m 27s
ubuntu-20.04 (package, non-mavsdk_server)	6m 17s
ubuntu-22.04 (package, non-mavsdk_server)	5m 18s
android-arm	5m 23s
android-arm64	5m 19s
linux-armv6	4m 58s
linux-armv7	4m 52s
linux-armv6-musl	11m 53s
android-x86	5m 27s
ios	6m 51s
android-x86_64	5m 23s
linux-arm64	4m 57s
ios_simulator	7m 36s
macOS	16m 13s
linux-armv7l-musl	11m 43s
macOS-framework	11m 36s
linux-arm64-musl	13m 44s
Windows	10m 48s
ubuntu-22.04 (style and proto check)	1m 19s
iOS XCFramework	1m 1s
	3h 16m 26s

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