Merge branch 'staging' into 'production'

.gitlab-ci.yml

README.rst

docs/source/dev/README.rst

docs/source/index.rst

docs/source/user/README.rst

morph/README.rst

morph/grid/local/README.rst

morph/grid/local/Vagrantfile

morph/grid/local/config.json

morph/grid/local/grid.nix

morph/grid/local/vagrant-guest.nix

morph/grid/local/virtual-hardware.nix

morph/grid/production/.gitignore

morph/grid/production/config.json

morph/grid/production/grid.nix

morph/grid/production/users.nix

morph/grid/testing/.gitignore

morph/grid/testing/config.json

morph/grid/testing/grid.nix

morph/grid/testing/users.nix