Add bug report template (#617)

This bug report template should help us and the reporting person to communicate more efficiently.

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,23 @@
+---
+name: Bug report
+about: Create a report to help us improve
+title: "[BUG] "
+labels: ''
+assignees: ''
+
+---
+
+#### Code Sample, a copy-pastable example
+
+```python
+# Your code here
+
+```
+#### Bug description
+A clear and concise description of what the bug is.
+
+#### Expected Output
+A clear and concise description of what you expected to happen.
+
+#### Remarks
+A concise description of information that doesn't fit into the other categories (e.g. versions, dependencies etc.)