I saved the `file_types.json` file and got a diff because it had some
trailing whitespace. I ran
[`lineman`](https://github.com/JosephTLyons/lineman) on the codebase.
I've done this before, but this time, I've added in the following
settings to our `.zed` local settings, to make sure every future save
respects our desire to have consistent whitespace formatting.
```json
"remove_trailing_whitespace_on_save": true,
"ensure_final_newline_on_save": true
```
Release Notes:
- N/A
This PR extracts HTML support into an extension and removes the built-in
HTML support from Zed.
Release Notes:
- Removed built-in support for HTML, in favor of making it available as
an extension. The HTML extension will be suggested for download when you
open a `.html`, `.htm`, or `.shtml` file.
