Update submodule matrix to latest Thu Aug 29 00:42:01 UTC 2019
Update submodule matrix to latest Thu Aug 29 00:42:01 UTC 2019

    - matrix in PX4/Firmware (341c0ae739753db98dcd0711e91f621c1666b16d): https://github.com/PX4/Matrix/commit/56b069956da141da244926ed7000e89b2ba6c731
    - matrix current upstream: https://github.com/PX4/Matrix/commit/cc084e0791535e8426780e6a4f05794804db1b82
    - Changes: https://github.com/PX4/Matrix/compare/56b069956da141da244926ed7000e89b2ba6c731...cc084e0791535e8426780e6a4f05794804db1b82

    cc084e0 2019-08-26 Martina Rivizzigno - matrix: add method to check all values are nan (#82)
84b3da2 2019-08-22 kritz - Canonical Quaternion with tests (#81)

krbeverx/Firmware,acfloria/Firmware,dagar/Firmware,dagar/Firmware,krbeverx/Firmware,PX4/Firmware,acfloria/Firmware,PX4/Firmware,krbeverx/Firmware,dagar/Firmware,PX4/Firmware,krbeverx/Firmware,dagar/Firmware,acfloria/Firmware,krbeverx/Firmware,PX4/Firmware,dagar/Firmware,PX4/Firmware,acfloria/Firmware,dagar/Firmware,dagar/Firmware,krbeverx/Firmware,acfloria/Firmware,krbeverx/Firmware,PX4/Firmware,PX4/Firmware,acfloria/Firmware,acfloria/Firmware