Update Feature_request.md

Author: DanielRosenwasser

.github/ISSUE_TEMPLATE/Feature_request.md

@@ -32,8 +32,10 @@ What shortcomings exist with current approaches?
 ## Checklist
 
 My suggestion meets these guidelines:
-* [ ] This wouldn't be a breaking change in existing TypeScript / JavaScript code
+
+* [ ] This wouldn't be a breaking change in existing TypeScript/JavaScript code
 * [ ] This wouldn't change the runtime behavior of existing JavaScript code
 * [ ] This could be implemented without emitting different JS based on the types of the expressions
-* [ ] This isn't a runtime feature (e.g. new expression-level syntax)
+* [ ] This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, etc.)
+* [ ] This feature would agree with the rest of [TypeScript's Design Goals](https://github.com/Microsoft/TypeScript/wiki/TypeScript-Design-Goals).