servo: Merge #19542 - Add Windows as a development platform in Readme (from atouchet:readme-windows); r=jdm

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Source-Repo: https://github.com/servo/servo
Source-Revision: 0fa605d2439c4f640b7f180c18d768a7a14e7f1e

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : 498a62bafec0736638d14968d5a5ac90f9d7f1d8

servo/README.md

@@ -4,7 +4,7 @@
 
 Servo is a prototype web browser engine written in the
 [Rust](https://github.com/rust-lang/rust) language. It is currently developed on
-64-bit OS X, 64-bit Linux, and Android.
+64-bit OS X, 64-bit Linux, 64-bit Windows, and Android.
 
 Servo welcomes contribution from everyone.  See
 [`CONTRIBUTING.md`](CONTRIBUTING.md) and [`HACKING_QUICKSTART.md`](docs/HACKING_QUICKSTART.md)