Subdirectory to point to a branch #153

Hey!

I'm working on a repo, and there's currently a v2 branch which where we'd like to have separate docs to master. Locally I can get this working, but when pushing it to the repo it doesn't work.

1. First I made a v2 directory in master, with an index.html, where I point the bathPath to the branch (here):

basePath: 'https://raw.githubusercontent.com/wix/react-native-navigation/v2/docs/',

2. I make some files (no index.html) in the v2 branch (here).

3. Booting this locally I can now switch between the master docs (http://localhost:3000/#/) and the v2 docs (http://localhost:3000/v2/#/) fine.

4. Pushing this to the server, I get null content (https://wix.github.io/react-native-navigation/v2/#/). When I look at the network requests, it's trying to load the raw github content from:
   https://wix.github.io/raw.githubusercontent.com/wix/react-native-navigation/v2/docs/README.md

For some reason the wix.github.io is prepended to the URL, causing a 404.

Is this expected, or do I need to do something else? Cheers!