This is needed in some tests which are using exiv2json.
It seems that during metadata conversion, the dates are converted from the
original timezone (which seems to be saved in xmp) into the local time zone.
- add Vagrantfile to contrib/vms
- add custom provisioning via shell scripts
- move gitlab-ci before_script: to ci/install_dependencies.sh which is also used
by vagrant
- change COPR setup on CentOS 7 (yum-plugin-copr does not seem to work)
- add a GitLab CI configuration file to run a pipeline on the major Linux
distros
- add a build script that builds all build combinations of exiv2 & runs the test
suite
