Add color to output

[LPGhatguy]

I'm not sure if the Rust ecosystem has a good colorizing library that supports all platforms well (especially weird configurations like Windows with Git Bash via cmd.exe).

If there is one, we should add it to the Rojo binary and issue warnings, errors, and other information messages in cool colors to catch peoples' attention.

[LPGhatguy]

There are two libraries we could use for this, term and termcolor. The former is unmaintained as far as I understand, but the latter doesn't work on Windows (and thus breaks Cargo's coloring on current Rust nightly).

[LPGhatguy]

Okay, termcolor was fixed later today, hah.

[LPGhatguy]

Colored enough.