Create issue templates for bugs and feature-requests (#85)

I recently added issue and pull request templates to the proposals repo and it was suggested I do so for our other codebases.

Author: rylandg

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,25 @@
+---
+name: Bug report
+about: Report a bug or unexpected behavior with Temporal Java SDK
+title: ''
+labels: potential-bug
+assignees: ''
+
+---
+
+## Expected Behavior
+
+
+## Actual Behavior
+
+
+## Steps to Reproduce the Problem
+
+  1.
+  1.
+  1.
+
+## Specifications
+
+  - Version:
+  - Platform:

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,20 @@
+---
+name: Feature request
+about: Suggest an idea for the Temporal Java SDK
+title: ''
+labels: enhancement
+assignees: ''
+
+---
+
+**Is your feature request related to a problem? Please describe.**
+A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]
+
+**Describe the solution you'd like**
+A clear and concise description of what you want to happen.
+
+**Describe alternatives you've considered**
+A clear and concise description of any alternative solutions or features you've considered.
+
+**Additional context**
+Add any other context or screenshots about the feature request here.