Support CARGO_TERM_VERBOSE, etc.

[Alexhuszagh]

Checklist

• I've looked through the issues and pull requests for similar request
• This feature could be solved with a custom docker image (optional)

Describe your request

Currently, when extracting the verbose mode, quiet mode, or term color, we ignore the environment variables CARGO_TERM_COLOR, etc. These should be respected and parsed by cross itself.

Describe why this would be a good inclusion for cross

This is relatively easy to implement and is fully compatible with cargo.