We actually write to stderr by default, so:
bin >/dev/null
currently weirdly prints non-colorized output, whereas:
bin 2>log
weirdly prints colorized output to a file.
This merges all the bsd (including darwin) support into terminal_bsd.go
Cross-compiling works for all of them in that they all compile, but I've only
actually tested the binary on dragonflybsd. I don't see why this wouldn't
work on the others since I don't think they'd compile if they didn't
support TIOCGETA and Termios, but just a heads up.