Support for passing to CMake any random string

[lilianmoraru]

Currently, the crate limits the user on what kind of options he can pass to CMake. I am trying to pass -C path/to/a/cmake/script.cmake(it's a script that speeds-up build-times, I use it for all cmake projects) and it is just impossible to do that with the current API. I think there should be an option where the user can pass flags himself, whatever he wants.

[alexcrichton]

Seems reasonable to me! Would you be interested in sending a PR?

[lilianmoraru]

I could do that. What do you think would be the appropriate naming for these functions? I am thinking(inspired by std::process::Command) of: cmake_arg/cmake_args or arg/args? At least for me, arg/args seems too ambiguous.

[alexcrichton]

Yeah cmake_arg and cmake_args sounds good to me!