The 3.1.6 version of the libVDA5050++. It follows the VDA5050 2.1.0 standard.

Fixes:
- handle mqtt messages on unknown topics !4
- do not insert duplicate action ids as failed actions into the state !5
- fix TOCTOU race condition when validating/accepting orders !6
- report noOrderToCancel when receiving cancelOrder with no active order !7