Passing -vv argument to help debug cargo build scripts

[dherman]

From @jedireza on December 26, 2016 21:38

As mentioned in #159, cargo build script output is suppressed unless an error occurs. Should we add an argument or piggyback on the debug argument, so we can pass -vv to cargo?

Copied from original issue: neon-bindings/neon-cli#40

[dherman]

This would basically come along for free with the xargo-like wrapper. (See #242, #243, #244)

[kjvalencik]

Additional cargo arguments may be passed in both neon-cli and cargo-cp-artifact.