This change has refactored the illumos layer to make use of the
golang.org/x/sys/unix package to achieve a clean cgo-free solution
for illumos and Solaris.
The approach here should be a template for other systems. I've
also made some changes to the Linux port.
fixes#164 KeyEscape does not work in Go 1.9 under Linux
This is a complete refactor of the input loop for UNIX systems.
We use a blocking reader on the TTY, and a separate select
loop for timers and other events. This means that our idle
use should be low now.
