Revamped security-vulnerability.md

Additionally, removed the `:` where it used to say `Checklist:`. It now
just says `Checklist`.

.github/ISSUE_TEMPLATE/bug-report.md

@@ -36,7 +36,7 @@ Add any other context about the problem here.
 
 ___
 
-## Checklist:
+## Checklist
 
 - [ ] I have checked for similar issues.
 - [ ] This is a bug report, not a feature request, improvement request, or security vulnerability report.

.github/ISSUE_TEMPLATE/feature-request.md

@@ -22,7 +22,7 @@ Add any other context or screenshots about the feature request here.
 
 ___
 
-## Checklist:
+## Checklist
 
 - [ ] I have checked for similar issues.
 - [ ] This is a feature request, not an improvement request, bug report, or security vulnerability report.

.github/ISSUE_TEMPLATE/improvement-request.md

@@ -17,7 +17,7 @@ Add any other context or screenshots about the improvement request here.
 
 ___
 
-## Checklist:
+## Checklist
 
 - [ ] I have checked for similar issues.
 - [ ] This is an improvement request, not a feature request, bug report, or security vulnerability report.

.github/ISSUE_TEMPLATE/security-vulnerability.md

@@ -7,13 +7,17 @@ assignees: beanbeanjuice
 
 ---
 
-**__Describe the Security Vulnerability__**
+## Security Vulnerability Description
 A clear and concise description of what you want to happen.
 
-**__Additional Context__**
+___
+
+## Additional Context
 Add any other context or screenshots about the security vulnerability here.
 
-# Checklist:
+___
+
+## Checklist
 
 - [ ] I have checked for similar issues.
 - [ ] This is a security vulnerability report, not a feature request, improvement request, or a bug report.