Add an issue template (#49)

* Add an issue template

* fixup! Add an issue template

Author: superbrothers

.github/issue_template.md

@@ -0,0 +1,18 @@
+**Is this a BUG REPORT or FEATURE REQUEST?**:
+
+<!-- Delete only one line -->
+- bug
+- 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**:
+- Concourse CI version: (use `fly --version`):
+- kubernetes-resource image version:
+- Others: