Update ISSUE_TEMPLATE.md

Author: allenhwkim

ISSUE_TEMPLATE.md

@@ -1,10 +1,10 @@
-**IMPORTANT**
-Please be specific with an example
+**IMPORTANT**  
+_Please be specific with an example. An issue with no example or unclear requirements may be closed._
 
 **Steps to reproduce and a minimal demo**
 
   - _What steps should we try in your demo to see the problem?_
-  - Plunker example: ??? 
+  - _Plunker example_
   - _If you cannot reproduce an issue with a plunker example, it's your environmental issue_
 
 **Current behavior**