Add issue templates

.gitlab/issue_templates/Bug.md

+<!---
+Please read this!
+
+Before opening a new issue, make sure to skim through the documentation.
+--->
+
+### Summary
+
+(Summarise the bug encountered concisely.)
+
+### Environment
+
+- Python version (`python --version`):
+- OS: (`uname -a`)
+
+### What is the current *bug* behavior?
+
+(What actually happens)
+
+### What is the expected *correct* behavior?
+
+(What you should see instead)
+
+### Steps to reproduce
+
+(How one can reproduce the issue - this is very important.)
+
+### Relevant logs and/or screenshots
+
+(Paste any relevant logs - please use code blocks (put the code between ```) to format console output, logs, and code as it's very hard to read otherwise.)
+
+/label ~bug

.gitlab/issue_templates/Feature.md

+<!---
+Please read this!
+
+Before opening a new issue, make sure to skim through the documentation.
+--->
+
+### Summary
+
+(Summarise the feature and try to provide a usage example.)
+
+### What is the current workaround to achieve the same functionality?
+
+(Is there already a way to get the job done?)
+
+/label ~enhancement