native dependencies are not required during the build
document Makefile changes
Added missing stance check.
Merge pull request #7038 from Mailaender/packaging-tweaks

Reduced the Travis dependencies and adapted the installation instructions
Merge pull request #7049 from WolfGaming/FixUpgradeCrash

Added missing stance check.
Refactor Upgrade => Condition[Level], ...
Closes #7047
Rename some conditions