15.09-RC2

-- RELEASE-15.09-RC2 - First LibrePilot Release -- Supermoon Eclipse
This release candidate adds a fix for external magnetometer calibration.
It also fixes a build issue caused by broken make dependencies.

The list of bug fixes added in this release candidate is available here:
https://librepilot.atlassian.net/issues/?filter=10301

** Bug
    * [LP-135] - Aux mag calibration issue
    * [LP-136] - Build errors caused by broken uavobjgenerator make dependencies