failing test for spinning up multiple background processes
fix for the jobIndex counting
fix for setting the exit index properly
1.7.1
Basic working version of pushd
Handle pushd with no args and an empty stack
Handle pushd with no args

* Still need to add logic to "fix" stack when previous directory no longer exists
pushd now corrects the stack after a failed swap
I've made a huge mistake

* So it turns out that the first element in dirs is always pwd. This actually
simplified the implementation slightly. Hey, at least I'm learning :)
* Added more assertions to ensure that what's being output correctly reflects
the shell's state
Fixed error output bug
Handle +/-N arguments outside range
pushd with with working rotational argument support
Refactored pushd to aid readability
pushd no supports the -n option
Minor refactor
Adjusted a couple of tests

* Catch possible off-by-one errors in pushd +/-N
Ensure that pushd -n with no dir is a noop
nearly passing the jobs test with a bgdata backchannel hack
finally fixed the jobs test
1.8.0