Mozprocess is a process-handling module that provides some additional features
beyond those available with python’s subprocess:

 - better handling of child processes, especially on Windows
 - the ability to timeout the process after some absolute period, or some
 period without any data written to stdout/stderr
 - the ability to specify output handlers that will be called for each line
 of output produced by the process
 - the ability to specify handlers that will be called on process timeout
 and normal process termination
