Fix issue/PR templates & add sponsor button

Referenced in #1554, #1532, #1051

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,39 @@
+---
+name: "Bug report"
+about: "Something went wrong, please fix it!"
+title: "[BUG] "
+labels: "is:bug", "status:pending-review"
+---
+
+**Describe the bug**
+Begin with a short description of what the bug is.
+
+Some tips on writing a good bug report:
+- Explain what you expected to see and what actually happened
+- Include screenshots/casts of your issue, if possible
+- Add a link to your private config, if available
+- Expand on phrases like "it does not work" and clarify what commands are bound
+  on non-default keybinds.
+- Check your \*Messages\* buffer for warnings or errors (`SPC h e` or `M-x
+  view-echo-area-messages`).
+- Include a backtrace of the error, if possible. To acquire a backtrace, first
+  you must turn on `debug-on-error` then recreate the error. To do so, either:
+  - Turn on debug mode on the fly with `M-x toggle-debug-on-error`,
+  - Start Emacs with `emacs --debug-init`
+  - Or, if the error occurred while using `bin/doom`, use the `-d` or `--debug`
+    switches, or the `DEBUG` environment variable.
+- If the backtrace is especially long, put it in
+  <details><pre>...</pre></details> tags.
+
+
+**Steps to reproduce**
+1. Select these example steps,
+2. Delete them,
+3. And replace them with precise steps to reproduce your issue.
+4. Fill in "system information" below.
+
+
+**System information**
+<details><pre>
+Include the output of `M-x doom/info` or `~/.emacs.d/bin/doom info` here.
+</pre></details>

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,22 @@
+---
+name: "Feature Request"
+about: "Make suggestions for improving Doom Emacs"
+title: "[FEATURE] "
+labels: "is:request", "status:pending-review"
+---
+
+**Describe the feature**
+Summarize your suggestion or request.
+
+Include why it would be helpful and what type of user it would benefit most.
+
+If this feature is implemented in another editor or Emacs distro, please include
+screenshots or screencasts of it. If possible, include the names of the relevant
+commands and not just the keybinds to invoke them. Links to their implementation
+in source code would tremendously speed up processing of this request.
+
+
+**System information**
+<details><pre>
+Include the output of `M-x doom/info` or `~/.emacs.d/bin/doom info` here.
+</pre></details>

.github/ISSUE_TEMPLATE/howto.md

@@ -0,0 +1,26 @@
+---
+name: "How do I..."
+about: "How to get Doom to behave a certain way"
+title: "[HOWTO] "
+labels: "is:howto", "status:pending-review"
+---
+
+**What I want to achieve**
+Summarize what you are trying to do.
+
+Follow up with an expanded explanation, if necessary. A few suggestions of what
+you could include are:
+
+- Code or steps you've tried that did not yield the results you wanted,
+- Screenshots/casts of similar features in another editor or elsewhere,
+- Additional material or links to resources that could help clarify what you are
+  trying to do.
+- A link to your private config, if it is available publicly.
+- The names of commands available in other Emacs distros (rather than just the
+  keybinds that invoke them).
+
+
+**System information**
+<details><pre>
+Include the output of `M-x doom/info` or `~/.emacs.d/bin/doom info` here.
+</pre></details>

.github/ISSUE_TEMPLATE/question.md

@@ -0,0 +1,8 @@
+---
+name: "Question"
+about: "A question about the project or maintainer"
+title: "[QUESTION] "
+labels: "is:question", "status:pending-review"
+---
+
+What would you like to know?