Add merge request template

also assign ansible responsible to each ticket and mr by default

.gitlab/issue_templates/Bug.md

-Calling host: lasXXX.las.kit.edu (Fedora XX)
+Calling host: XXX.las.kit.edu (Fedora XX)
 
 Failing nodes: lasXXX, lasXXX
 
@@ -40,4 +40,4 @@ Possible fixes
 (If you can, link to the line of code that might be responsible for the problem)
 
 /label ~bug
-/cc @vn4918
+/assign @vn4918

.gitlab/issue_templates/Software-request.md

-Host: lasXXX.las.kit.edu
+Host: XXX.las.kit.edu
 
 OS: Fedora XX
 
@@ -12,4 +12,4 @@ Possibly also interesting for:
 -------------------------------
 
 /label ~softwarerequest ~suggestion
-/cc @project-manager
+/assign @project-manager

.gitlab/merge_request_templates/Default.md

+# Purpose / What's done
+
+(description of what this MR does.
+This can be the long description of a squash commit if one wants to squash the commits.)
+
+## Fixes issue
+
+Fixes issue #
+
+## Affects
+
+/label ~bug ~documentation ~feature
+
+# Quality assurance
+
+The following criteria are matched:
+
+* [ ] Local test with one computer succeeded
+* [ ] Test of sites.yml seucceeded
+* [ ] ansible-playbook --check ran successfully
+* [ ] README is updated or does not have to be updated
+
+/assign @vn4918