v0.42.0

Features:

• Add SET_MESSAGE_INTERVAL support to telemetry_server publish functions (#1497).
• Handle MAV_CMD_REQUEST_AUTOPILOT_CAPABILITIES requests as an autopilot (#1494).
• Add action_server implementation (#1491).
• Add mission_raw_server (#1488).
• Add telemetry_server plugin (#1482).

Bugfixes:

• Fix two warnings recently introduced (#1501).
• core: fix autopilot detection (#1490).

Enhancements:

• Various commication fixes (#1502).
• proto: update submodule (#1500).
• core: fix mission transfer unit tests (#1495).
• core/plugins: detect autopilot at runtime (#1489).
• Examples cleanup (#1449).

Contributors:

@bazfp, @julianoes