Add a option to support relative path in place of baseUrl

[DevSrSouza]

In my work, we are using S3 to deploy your SDKs and with it the documentation generated by Orchid for the specific version. We ship the documentation in a zip folder too for download, but because the project doesn't have relative path support for that, the user can't open the documentation in his computer.

Other problem related to that is the links from the Orchid, doesn't support to link directly to index.html of the folders causing other problem viewing the docs.

Could be awesome to see this two features.