Add bug report and enhancement issue templates (#722)

* Add bug report and enhancement issue templates

Signed-off-by: Thane Thomson <connect@thanethomson.com>

* Update .github/ISSUE_TEMPLATE/bug-report.md

Co-authored-by: Greg Szabo <16846635+greg-szabo@users.noreply.github.com>

* Clarify heading to include "definition of done" terminology

Signed-off-by: Thane Thomson <connect@thanethomson.com>

Co-authored-by: Greg Szabo <16846635+greg-szabo@users.noreply.github.com>

.github/ISSUE_TEMPLATE/bug-report.md

@@ -0,0 +1,28 @@
+---
+name: Bug report
+about: Create a report to help us squash bugs!
+labels: bug
+---
+<!--
+
+Please give us an overview of what went wrong, and what you expected to happen instead.
+
+-->
+
+**Steps to reproduce**
+
+<!--
+
+Please provide step-by-step instructions as to how to reproduce the problem.
+
+-->
+
+**What's the definition of "done" for this issue?**
+
+<!--
+
+Please describe clear and practical acceptance criteria for this issue. Anyone
+in the team should be able to look at this issue and determine whether or not
+the bug's been fixed.
+
+-->

.github/ISSUE_TEMPLATE/enhancement.md

@@ -0,0 +1,21 @@
+---
+name: Enhancement
+about: A request for a new feature, or to enhance existing functionality
+labels: enhancement
+---
+<!--
+
+Please describe the enhancement you would like to see implemented in
+tendermint-rs. Give as much context as possible.
+
+-->
+
+**What's the definition of "done" for this issue?**
+
+<!--
+
+Please describe clear and practical acceptance criteria for this issue. Anyone
+in the team should be able to look at this issue and determine whether or not
+the new feature/enhancement has been implemented.
+
+-->