Write colored strings with ANSI escape code into a `termcolor` terminal.
This package provides a single function, [`write_ansi`], which parses ANSI
escape codes in the provided byte string and transforms them into the
corresponding `termcolor` commands. The colors will be supported even on a
Windows console.
The main purpose of this package is to forward colored output from a child
process.
```rust
extern crate termcolor;
extern crate fwdansi;
use termcolor::*;
use std::io;
use std::process::Command;
use fwdansi::write_ansi;
fn main() -> io::Result<()> {
let output = Command::new("rustc").args(&["--color", "always"]).output()?;
let mut stderr = StandardStream::stderr(ColorChoice::Always);
write_ansi(&mut stderr, &output.stderr)?;
//^ should print "error: no input filename given" with appropriate color everywhere.
Ok(())
}
```