cmake organize code coverage handling and base

.gitignore

.travis.yml

CMakeLists.txt

Makefile

Tools/docker_run.sh

cmake/common/coverage.cmake

cmake/common/px4_base.cmake

cmake/common/px4_git.cmake

cmake/common/px4_metadata.cmake

cmake/common/px4_upload.cmake

cmake/common/sanitizers.cmake

posix-configs/SITL/init/test/test_template.in

src/firmware/nuttx/CMakeLists.txt

src/firmware/posix/CMakeLists.txt

src/firmware/posix/sitl_tests.cmake

src/firmware/qurt/CMakeLists.txt

src/modules/systemlib/mixer/mixer_helicopter.cpp

src/modules/systemlib/mixer/mixer_multirotor.cpp

src/modules/uavcanesc/CMakeLists.txt

src/modules/uavcannode/CMakeLists.txt