Add vcpkg installation instructions

Author: PhoebeHui

README.md

@@ -250,6 +250,19 @@ Otherwise you can do the regular autotools dance:
 make install
 ```
 
+Alternatively, you can build and install restclient-cpp using [vcpkg](https://github.com/microsoft/vcpkg/) dependency manager:
+
+```bash
+git clone https://github.com/Microsoft/vcpkg.git
+cd vcpkg
+./bootstrap-vcpkg.sh
+./vcpkg integrate install
+./vcpkg install restclient-cpp
+```
+
+The restclient-cpp port in vcpkg is kept up to date by Microsoft team members and community contributors.
+If the version is out of date, please [create an issue or pull request](https://github.com/Microsoft/vcpkg) on the vcpkg repository.
+
 ## Contribute
 All contributions are highly appreciated. This includes filing issues,
 updating documentation and writing code. Please take a look at the