Restrict the number of stack inputs and outputs to 16

[bobbinth]

Currently, we allow users to specify an arbitrary number of stack inputs and outputs. This adds quite a bit of complexity to the constraint system (i.e., needing to manage the initial and final states of the stack overflow table). Moreover, practical benefit of this capability are limited (and in some ways, may be actually detrimental).

So, I think we should remove the ability to provide an arbitrary number of stack inputs/outputs and instead limit these values to 16.

As a part of this, we should also make sure all documentation related to the stack overflow table is up to date.

[bobbinth]

Most of this has been addressed in #1456 - but we still need to update the documentation before we can close this issue.

[bobbinth]

Closed by #1456 and #1530.