add feature request template

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,20 @@
+---
+name: Feature request
+about: Suggest an feature/improvement to SatDump
+title: ''
+labels: enhancement
+assignees: ''
+
+---
+
+**What would you want to be added to satdump?**
+A clear and concise description of what the idea/problem is.
+
+**Describe the feature you'd like to have**
+A clear and concise description of what you want to happen.
+
+**Describe alternatives you've considered**
+A clear and concise description of any alternative solutions or features you've considered.
+
+**Additional context**
+Here you can for provide more information about what you'd like to see as the end result. Feel free to also post images if you have ideas regarding the UI