Revise issue templates.

.github/ISSUE_TEMPLATE/bug_report.md

@@ -4,7 +4,7 @@ about: Bugs, build errors, compatibility/stability issues
 
 ---
 
-<--
+<!--
 To file a bug report, fill out the form below.
 Use a descriptive title that best explains the bug in one sentence.
 Attach screenshots if the bug is visual.
@@ -21,6 +21,10 @@ Operating system:
 Rack version: vX.X.X
 Hardware relevant to your issue (e.g. graphic card model, audio/MIDI device):
 
-### Expected behavior
+### Summary
 
-### Actual behavior
+### Steps to reproduce
+
+<!--
+If developers cannot reproduce the bug, it cannot be fixed.
+-->

.github/ISSUE_TEMPLATE/feature_request.md

@@ -4,18 +4,22 @@ about: Feature ideas, design proposals
 
 ---
 
-<--
+<!--
 To request a feature, fill out the form below.
 Use a descriptive title that best explains the feature request in one sentence.
 -->
 
 ### Summary
 
+<!--
 What is the motivation for this feature? What does the feature achieve?
+-->
 
 ### Proposed design
 
+<!--
 What is one possible implementation of this feature?
 If visual, explain how the user interface should be changed. If interactive, explain the steps needed for a user to use the feature.
 Are there any corner cases where your implementation would fail?
 Are there alternative implementations?
+-->