Squashed 'CMakeModules/' changes from 12d2b25..dd92677

dd92677 Adds default APK target that is always built.
9d8dd00 Adds missing include to def_apk.cmake

git-subtree-dir: CMakeModules
git-subtree-split: dd9267715715bf2fbdf75759e8c94fa65af9c063
Merge commit '8bb4d31d04171d0a420c51fb91abbd944f8620de'
Adds AndroidLogger.
Adds standard deviation to Pose.proto
Adds docs to Logger.
Adds logging to AndroidLogger.