* add todo for docker wait
* add makefile target to scan containers with trivy
* pin version of trivy in travis file
* add trivy cache to persistent storage of travis (commented since not part of ci for the moment)
* reorg travis file + remove goss as it is not used
* add a fixed version for the base image
* add file with tags to gitignore
* introduce tag-all target
* remove after_failure step
* add ignore file for trivy
* store the tag for the builder as well
* remove tag_file after completing scans
* replace manual build and publish commands with generated ones
* update kdav builder to resolve CVE-2019-3855
* ignore CVE-2019-3855 which is thrown in kdav build container
* exclude the build-webapp-demo from build-all
