[Pull Request] Add --clone-full option to bench init

Hi,

Bench is doing shallow clones by default, which is fine for production, but not ideal if we want to set up a development environment.
I created a PR for bench that adds a new option --clone-full to bench init. If specified, bench will do full clones instead of shallow ones.

Here is the PR: https://github.com/frappe/bench/pull/1113

I am not sure what is the right process to request a review for this.