Auto merge of #11184 - perlun:patch-1, r=mbrubeck

Added info about browserhtml

- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes do not require tests because it is only Markdown documentation.

Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process.

----

I feel it would make sense to make mention of this here, especially since Browser.html is part of the [road map](https://github.com/servo/servo/wiki/Roadmap) for what we aim to achieve during the year.

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README.md

@@ -159,7 +159,9 @@ cp servobuild.example .servobuild
 
 ## Running
 
-Use `./mach run [url]` to run Servo.
+Use `./mach run [url]` to run Servo. Also, don't miss the info on the [browserhtml page](https://github.com/browserhtml/browserhtml) on how to run the Browser.html
+full tech demo (it provides a more browser-like experience than just browsing a single
+URL with servo).
 
 
 ### Commandline Arguments