Update issue templates (#159)

.github/ISSUE_TEMPLATE/bug-report.md

@@ -2,7 +2,7 @@
 name: Bug report
 about: Create a report to help us improve
 title: 'Bug: Helpful but short description'
-labels: ''
+labels: bug
 assignees: ''
 
 ---

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,20 @@
+---
+name: Feature request
+about: Suggest an idea for this project
+title: 'Feature: Short description of the request'
+labels: enhancement
+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.