make: reintroduce dependency from flash to all
travis: first executing shorter running scripts
travis: exit early on error
Merge pull request #2037 from OlegHahm/travis_change_order

travis: first executing shorter running scripts
Merge pull request #2043 from LudwigOrtmann/flash-all-again

make: reintroduce dependency from flash to all
ignore IDEA project files
Merge pull request #2055 from MatthiasLohr/ignore-idea

ignore IDEA project files