add issue template

ISSUE_TEMPLATE.md

@@ -0,0 +1,35 @@
+<!-- Thanks for reporting an issue! Please make sure you fill out the blanks below with as much detail as possible. -->
+
+## Summary
+
+<!-- What's wrong? 1-2 sentence summary here. -->
+
+## Expected Result
+
+<!-- What did you expect to happen?-->
+
+## Steps to Reproduce
+
+<!-- Provide as much detail as possible, so that anyone can reproduce the issue. -->
+
+1. …
+2. …
+3. …
+
+
+## Logs, errors, diagnostics, etc
+
+
+
+<!-- If it’s long, please paste to https://gist.github.com/ and insert the link here. -->
+
+
+## Extra information
+
+<!-- Any other comments? -->
+
+
+## Versions
+
+- **LDA Version:** ...
+- **Operating System:** ...