* add docker pull to warm up build cache on travis
* explicitly build multi stage build stages
* make create repo script dynamic in the choice of the distribution
* add hadolint for dockerfile linting
* add hadofile config
* add checks for dockerfiles and shellcheck into makefile
* shellcheck fixes
* add workaround so that .env can be sourced again from version.sh
* hadolint fixes
* print progress of build/run.sh
* fix check for jq in setup.sh
relates to #41 and #26
* add a kdav image
* do not install composer into the docker image
instead use a multi stage build that copies the resulting directory into the final image
* set default version in compose
resolves#54
