Merge branch 'develop' of https://github.com/nlohmann/json into develop

.github/ISSUE_TEMPLATE/Bug_report.md

 ---
 name: Bug report
 about: Create a report to help us improve
+title: ''
+labels: 'kind: bug'
+assignees: ''
 
 ---
 

.github/ISSUE_TEMPLATE/Feature_request.md

 ---
 name: Feature request
 about: Suggest an idea for this project
+title: ''
+labels: 'kind: enhancement/improvement'
+assignees: ''
 
 ---
 

.github/ISSUE_TEMPLATE/question.md

+---
+name: Question
+about: Ask a question regarding the library.
+title: ''
+labels: 'kind: question'
+assignees: ''
+
+---
+
+- Describe what you want to achieve.
+
+- Describe what you tried.
+
+- Describe which system (OS, compiler) you are using.
+
+- Describe which version of the library you are using (release version, develop branch).