Create a GitHub issue template

Based on https://github.com/kubernetes/kubernetes/blob/master/.github/ISSUE_TEMPLATE.md



Signed-off-by: Levi Blackstone <levi.blackstone@rackspace.com>

.github/ISSUE_TEMPLATE.md

+<!-- This form is for bug reports and feature requests ONLY!
+-->
+
+**Is this a BUG REPORT or FEATURE REQUEST?**:
+
+> Uncomment only one, leave it on its own line:
+>
+> /kind bug
+>
+> /kind feature
+
+
+**What happened**:
+
+**What you expected to happen**:
+
+**How to reproduce it (as minimally and precisely as possible)**:
+
+
+**Anything else we need to know?**:
+
+**Environment**:
+- ksonnet version (use `ks version`):
+- Kubernetes version (use `kubectl version`):