v5.0 Release

This is the v5.0 stable release including support for FMUv4 hardware.

PX4 Bootloader 4.1 RC2

This is a release candidate for the 4.1 release. The current version 4.0 has the same API.

Change notes:

• libopencm3 update, provides relevant USB bugfixes, which particularly helps on Windows.
• mavstation support