Add merge request template

Author: revig

.gitlab/merge_request_templates/MERGE_REQUEST_TEMPLATE.md

@@ -0,0 +1,24 @@
+### Requirements
+
+-   Filling out this template is mandatory. Please provide sufficient information so that the request can be reviewed in a timely manner.
+-   Please thoroughly test your code to ensure against regressions.
+
+### Description of the Change or Addition
+
+<!--
+
+This description should give a good idea of what your code will be doing, it should make the design of your change easily comprehensible.
+
+-->
+
+### Possible Side-Effects
+
+<!-- What are the possible negative impacts of your code change? -->
+
+### Verification
+
+<!--
+
+How did you verify that all new functionality has the expected effects without introducing any regressions?
+
+-->