want to add a post install script to make python-rclone more flexible

[MrLYG]

Hi @ddragosd, Recently, our project need use rclone to sync files to remote storage. Before Using our package, Users have to install rclone on their local machine is definitely a bad experience. We write a script to dynamically install rclone which is based on the user's operating system. That's means when a user runs the command pip install [our package name] , there a script will be automated run to install rclone to the package directory. So that we can directly use the binary file or .exe file to use functions supplied by rclone.

And now we need to write APIs to wrapper rclone for convenient use it. and then I find your repository, it is awesome. I like your project; this is great work. and it is very useful for our team. So I want to make it more flexible and also more fit for my team. Could I submit a PR for you, to make your project get rid of the dependency which the user must install rclone before using your project?