Update issue templates (#6784)

* Update issue templates

Differentiate between bug and feature requests. Also cleans up/updates the existing bug report template.

* Update bug_report.md

* Delete ISSUE_TEMPLATE.md

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,40 @@
+---
+name: Bug report
+about: Create a report to help us improve F#
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+Please provide a succinct description of the issue.
+
+**Repro steps**
+
+Provide the steps required to reproduce the problem:
+
+1. Step A
+2. Step B
+
+If possible attach a zip file with the repro case. This often makes it easier for others to reproduce.
+The zip file should ideally represent the situation just before the call/step that is problematic.
+
+**Expected behavior**
+
+Provide a description of the expected behavior.
+
+**Actual behavior**
+
+Provide a description of the actual behaviour observed. 
+
+**Known workarounds**
+
+Provide a description of any known workarounds.
+
+**Related information**
+
+Provide any related information (optional):
+
+* Operating system
+* .NET Runtime kind (.NET Core, .NET Framework, Mono)
+* Editing Tools (e.g. Visual Studio Version, Visual Studio)

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,20 @@
+---
+name: Feature request
+about: Suggest an idea for the F# tools or compiler
+title: ''
+labels: Feature Request
+assignees: ''
+
+---
+
+**Is your feature request related to a problem? Please describe.**
+A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]
+
+**Describe the solution you'd like**
+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**
+Add any other context or screenshots about the feature request here.