Revamped GitHub Issue templates

.github/ISSUE_TEMPLATE/Bug_report.md

@@ -4,11 +4,16 @@ about: Create a report to help us improve
 
 ---
 
+<!--
+If you don't know how to get some of the following information from your computer, visit:
+https://flameshot.js.org/#/data/issue-reporting
+-->
+
 **Flameshot version**
 <!-- Version or commit. -->
 
 **Describe the bug**
-<!-- A clear and concise description of what the bug is. -->
+<!-- A clear and concise description of what the bug is. Add screenshots if it helps explaining the issue. -->
 
 **To Reproduce**
 <!-- Steps to reproduce the behaviour. -->

.github/ISSUE_TEMPLATE/Feature_request.md

@@ -5,5 +5,10 @@ about: Suggest an idea for this project
 ---
 
 **Is your feature request related to a problem?**
+<!--
 A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]
-Please, a single feature per issue.
+Please make sure:
+- a single feature per issue
+- explain in detail what you have in mind
+- if it helps, add sketches/pictures
+-->