Match indentation style
Add an object-oriented wrapper for Unix child processes
Allow file descriptors to read a finite amount
Set close-on-exec flag to keep fd's from getting leaked to bash
Add object-oriented wrapper for Unix signals
Make forked-ferry use the new abstractions
Save and restore terminal state, even if shell exits uncleanly
Run the user's shell instead of hardcoding bash
Rename ferry to simple-ferry
Factor out Ferry into its own .hh and .cc files