[meta] Update ISSUE_TEMPLATE.md

Remove the need to indent terminal output by using headings instead of a list.
Simplify formulation of steps

Author: guidobouman

.github/ISSUE_TEMPLATE.md

@@ -1,42 +1,44 @@
 
 <!-- Thank you for being interested in nvm! Please help us by filling out the following form if you‘re having trouble. If you have a feature request, or some other question, please feel free to clear out the form. Thanks! -->
 
-- Operating system and version:
+#### Operating system and version:
 
-- `nvm debug` output:
-  <details>
-  <!-- do not delete the following blank line -->
+#### `nvm debug` output:
+<details>
+<!-- do not delete the following blank line -->
 
-  ```sh
+```sh
 
-  ```
-  </details>
+```
+</details>
 
-- `nvm ls` output:
-  <details>
-  <!-- do not delete the following blank line -->
+#### `nvm ls` output:
+<details>
+<!-- do not delete the following blank line -->
 
-  ```sh
+```sh
 
-  ```
-  </details>
+```
+</details>
 
-- How did you install `nvm`? (e.g. install script in readme, Homebrew):
+#### How did you install `nvm`?
+<!-- (e.g. install script in readme, Homebrew) -->
 
-- What steps did you perform?
+#### What steps did you perform?
 
-- What happened?
+#### What happened?
 
-- What did you expect to happen?
+#### What did you expect to happen?
 
-- Is there anything in any of your profile files (`.bashrc`, `.bash_profile`, `.zshrc`, etc) that modifies the `PATH`?
+#### Is there anything in any of your profile files that modifies the `PATH`?
+<!--  (e.g. `.bashrc`, `.bash_profile`, `.zshrc`, etc) -->
 
-<!-- if this does not apply, please delete this section -->
-- If you are having installation issues, or getting "N/A", what does `curl -I --compressed -v https://nodejs.org/dist/` print out?
-  <details>
-  <!-- do not delete the following blank line -->
+<!-- Please remove the following section if it does not apply to you -->
+#### If you are having installation issues, or getting "N/A", what does `curl -I --compressed -v https://nodejs.org/dist/` print out?
+<details>
+<!-- do not delete the following blank line -->
 
-  ```sh
+```sh
 
-  ```
-  </details>
+```
+</details>