Merge pull request DSpace#3008 from tdonohue/port_2863_to_7x

[Port dspace-7_x] Added Arabic Translation

Author: tdonohue

config/config.example.yml

@@ -176,6 +176,9 @@ languages:
   - code: en
     label: English
     active: true
+  - code: ar
+    label: العربية
+    active: true
   - code: ca
     label: Català
     active: true