Update README.

Author: taj-p

README.md

@@ -450,6 +450,8 @@ From there you can use pip to install it:
 `pip install ./dist/pact-python-N.N.N.tar.gz`
 
 ## Offline Installation of Standalone Packages
+
+Although all Ruby standalone applications are predownloaded into the wheel artifact, it may be useful, for development, purposes to install custom Ruby binaries. In which case, use the `bin-path` flag.
 ```
 pip install pact-python --bin-path=/absolute/path/to/folder/containing/pact/binaries/for/your/os
 ```