chore: update issue templates (#3600)

* chore: update issue templates
* chore: add a sentence for private repo investigation

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,66 @@
+---
+name: Bug report
+about: Something isn't working as expected
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+<!-- NOTE:
+
+If you find that markdown files are not rendered as expected, please go to https://marked.js.org/demo/ to see if it can be reproduced there. If it can be reproduced, please file a bug to https://github.com/markedjs/marked.
+
+If you want help on your bug, please also send us the git repository (GitHub, GitLab, Bitbucket etc...) where your hexo code is stored. It would greatly help. If you prefer not to have your hexo code out in public, please upload to a private GitHub repository and grant read-only access to hexojs/core.
+
+-->
+
+## Check List
+
+Please check followings before submitting a new issue.
+
+- [ ] I have already read [Docs page](https://hexo.io/docs/) & [Troubleshooting page](https://hexo.io/docs/troubleshooting)
+- [ ] I have already searched existing issues and they are not help  to me
+- [ ] I examined error or warning messages and it's difficult to solve
+- [ ] Node.js is higher than 6.9
+
+## Expected behavior
+
+## Actual behavior
+
+## How to reproduce?
+
+* Step1
+* Step2
+* etc...
+
+## Environment & Settings
+
+**Node.js & npm version**
+
+```
+```
+
+**Your site `_config.yml`** (Optional)
+
+```
+```
+
+**Your theme `_config.yml`** (Optional)
+
+```
+```
+
+**Hexo and Plugin version(`npm ls --depth 0`)**
+
+```
+```
+
+**Your package.json `package.json`**
+
+```
+```
+
+## Others
+
+<!-- If you have other information. Please write here. -->

.github/ISSUE_TEMPLATE/feature-request-improvement.md

@@ -0,0 +1,23 @@
+---
+name: Feature request / Improvement
+about: I have a feature request, suggestion, improvement etc...
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+## Check List
+
+Please check followings before submitting a new feature request.
+
+- [ ] I have already read [Docs page](https://hexo.io/docs/)
+- [ ] I have already searched existing issues
+
+## Feature Request
+
+<!-- Feature Request description -->
+
+## Others
+
+<!-- If you have other information. Please write here. -->

.github/ISSUE_TEMPLATE/other.md

@@ -0,0 +1,57 @@
+---
+name: Other
+about: Not a question, feature-request, bug
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+<!-- NOTE:
+
+If you find that markdown files are not rendered as expected, please go to https://marked.js.org/demo/ to see if it can be reproduced there. If it can be reproduced, please file a bug to https://github.com/markedjs/marked.
+
+If you want help on your bug, please also send us the git repository (GitHub, GitLab, Bitbucket etc...) where your hexo code is stored. It would greatly help. If you prefer not to have your hexo code out in public, please upload to a private GitHub repository and grant read-only access to hexojs/core
+
+-->
+
+## Check List
+
+Please check followings before submitting a new issue.
+
+- [ ] I have already confirmed other issue template and they are not different my want
+
+## Information
+
+<!-- Question description -->
+
+## Environment & Settings
+
+**Node.js & npm version**
+
+```
+```
+
+**Your site `_config.yml`** (Optional)
+
+```
+```
+
+**Your theme `_config.yml`** (Optional)
+
+```
+```
+
+**Hexo and Plugin version(`npm ls --depth 0`)**
+
+```
+```
+
+**Your package.json `package.json`**
+
+```
+```
+
+## Others
+
+<!-- If you have other information. Please write here. -->

.github/ISSUE_TEMPLATE/question-help.md

@@ -0,0 +1,60 @@
+---
+name: Question/Help
+about: I have a question, help for hexo (e.g. Customize)
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+<!-- NOTE:
+
+If you find that markdown files are not rendered as expected, please go to https://marked.js.org/demo/ to see if it can be reproduced there. If it can be reproduced, please file a bug to https://github.com/markedjs/marked.
+
+If you want help on your bug, please also send us the git repository (GitHub, GitLab, Bitbucket etc...) where your hexo code is stored. It would greatly help. If you prefer not to have your hexo code out in public, please upload to a private GitHub repository and grant read-only access to hexojs/core
+
+-->
+
+## Check List
+
+Please check followings before submitting a new issue.
+
+- [ ] I have already read [Docs page](https://hexo.io/docs/) & [Troubleshooting page](https://hexo.io/docs/troubleshooting)
+- [ ] I have already searched existing issues and they are not help to me
+- [ ] I examined error or warning messages and it's difficult to solve
+- [ ] Node.js is higher than 6.9
+
+## Question
+
+<!-- Question description -->
+
+## Environment & Settings
+
+**Node.js & npm version**
+
+```
+```
+
+**Your site `_config.yml`** (Optional)
+
+```
+```
+
+**Your theme `_config.yml`** (Optional)
+
+```
+```
+
+**Hexo and Plugin version(`npm ls --depth 0`)**
+
+```
+```
+
+**Your package.json `package.json`**
+
+```
+```
+
+## Others
+
+<!-- If you have other information. Please write here. -->