Update issue templates (#34)

Adding issue template for bug request per discussion on #27

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,28 @@
+---
+name: Bug report
+about: Create a report to help us improve
+title: "[BUG]"
+labels: ''
+assignees: andyphillipsgs
+
+---
+
+**Describe the bug**
+A clear and concise description of what the bug is.
+
+**To Reproduce**
+Steps to reproduce the behavior with code example.
+
+**Expected behavior**
+A clear and concise description of what you expected to happen.
+
+**Screenshots**
+If applicable, add screenshots to help explain your problem.
+
+**Systems setup:**
+ - OS: [e.g. Windows 10]
+ - Python version
+ - GS-Quant version [e.g. 0.7]
+
+**Additional context**
+Add any other context about the problem here.