Merge pull request AppImage#1034 from AppImage/fix-1032

0755 permissions for directories, addresses AppImage#1032

Merge pull request AppImage#953 from AppImage/extract-and-run-env-var

Allow using extract-and-run via environment variable

Update .travis.yml

Cosmetic fix for message

feature/usage

Merge pull request AppImage#359 from orivej/build-debug

Support debug build

Merge pull request AppImage#354 from darealshinji/patch-1

avoid unneeded if-statements, initializer fixes

Decrease verbosity, no false alarms

Overwrite $APPIMAGE and $APPDIR if they already exist, closes AppImag…

…e#66

Revert "Added wizardless commands (pack and unpack)" and re-implement…

… original solution; add USAGE