Merge branch 'develop' into 'master'

.gitattributes

.gitlab-ci.yml

Makefile

README.md

magento2-unit-test/latest/Dockerfile

magento2-unit-test/latest/php.ini

magento2-xml-lint/latest/Dockerfile

magento2-xml-lint/latest/docker-entrypoint

magento2-xml-lint/latest/xml-lint

php-lint/5.6/Dockerfile

php-lint/7.0/Dockerfile

php-lint/7.1/Dockerfile

php-lint/7.2/Dockerfile

php-lint/docker-entrypoint

php-lint/php-lint

static-code-analysis/Dockerfile

static-code-analysis/entrypoint.sh