Update ISSUE_TEMPLATE.md

Some changes to hopefully reduce help requests.
Added macOS to the list of operating systems.

.github/ISSUE_TEMPLATE.md

@@ -1,9 +1,11 @@
-(*** This section is for bug reports and feature requests only. This is NOT a help site. Do not ask help questions here. If you need help, please use stackoverflow. ***)
-
 ##### Description of the problem 
 
-Describe the problem/request in detail.
-Code snippet, screenshot, and small-test help us understand.
+This form is for three.js bug reports and feature requests only.
+This is NOT a help site. Do not ask help questions here.
+If you need help, please use stackoverflow.
+
+Describe the bug or feature request in detail.
+A code snippet, screenshot, and small-test help us understand.
 
 You can edit for small-test.
 http://jsfiddle.net/akmcv7Lh/ (current revision)
@@ -26,9 +28,10 @@ http://jsfiddle.net/hw9rcLL8/ (dev)
 
 - [x] All of them
 - [ ] Windows
+- [ ] macOS
 - [ ] Linux
 - [ ] Android
-- [ ] IOS
+- [ ] iOS
 
 ##### Hardware Requirements (graphics card, VR Device, ...)