Add linting

!6 (merged), but for the right branch (see also !7 (merged))

.gitlab-ci.yml

@@ -29,6 +29,7 @@ PHPunit:PHP5.3:MySQL:
   services:
     - mysql:5.6
   script:
+    - find . -type "f" -iname "*.php" | xargs -L "1" php -l
     - phpcs -n
     - phpunit
 
@@ -37,6 +38,7 @@ PHPunit:PHP5.6:MySQL:
   services:
     - mysql:5.6
   script:
+    - find . -type "f" -iname "*.php" | xargs -L "1" php -l
     - phpcs -n
     - phpunit
 
@@ -45,6 +47,7 @@ PHPunit:PHP7.0:MySQL:
   services:
     - mysql:5.6
   script:
+    - find . -type "f" -iname "*.php" | xargs -L "1" php -l
     - phpcs -n
     - phpunit
 
@@ -53,6 +56,7 @@ PHPunit:PHP7.1:MySQL:
   services:
     - mysql:5.6
   script:
+    - find . -type "f" -iname "*.php" | xargs -L "1" php -l
     - phpcs -n
     - phpunit
 
@@ -61,5 +65,6 @@ PHPunit:PHP7.2:MySQL:
   services:
     - mysql:5.6
   script:
+    - find . -type "f" -iname "*.php" | xargs -L "1" php -l
     - phpcs -n
     - phpunit