add PHP gitlab-ci examples

examples/PHP.md

+# PHP examples of .gitlab-ci.yml
+
+## Standard PHP app with lint and SonarQube analysis
+
+```
+# To use this script, you must have the following variables defined
+# You can define them at the project or the group level
+#
+# SONAR_URL:   Full URL to the SonarQube server
+# SONAR_TOKEN: API token for SonarQube
+
+variables:
+  GITLAB_CI: 1
+
+stages:
+  - test
+
+PHP Lint:
+  stage: test
+  image: its-registry.unl.edu/unl-its/docker-ci/php-lint:7.0
+  tags:
+  - docker
+  script:
+    - php-lint -d ./
+
+SonarQube:
+  stage: test
+  image: its-registry.unl.edu/unl-its/docker-ci/static-code-analysis:php
+  tags:
+  - docker
+  only:
+  - develop
+  script:
+  - sonar-scanner -Dsonar.host.url=$SONAR_URL -Dsonar.projectKey=$CI_PROJECT_PATH_SLUG -Dsonar.sources=. -Dsonar.login=$SONAR_TOKEN
+```