Add GitHub issue templates (#1423)

Add GitHub issue templates

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,24 @@
+---
+name: Bug report
+about: Report a problem with Vienna
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+**Describe the bug**
+A clear and short description of what the bug is.
+
+**To Reproduce**
+Steps to reproduce the behaviour, if possible.
+
+**Screenshots**
+Add screenshots to help explain your problem, if possible.
+
+**Please complete the following information:**
+ - Vienna version [e.g. 2.7.0]
+ - OS version: [e.g. macOS 11.1]
+
+**Additional information:**
+In which version of Vienna does the problem not occur, if applicable.

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,20 @@
+---
+name: Feature request
+about: Suggest an idea for Vienna
+title: ''
+labels: 'feature request :bulb:'
+assignees: ''
+
+---
+
+**Is your feature request related to a problem? Please describe.**
+A clear and short description of what the problem is.
+
+**Describe the solution you would like**
+A clear and short description of what you want to happen.
+
+**Describe alternatives you have considered**
+A clear and short description of any alternative solutions or features you have considered.
+
+**Additional context**
+Add any other context or screenshots about the feature request here.