We're abusing the current ASCII driver by telling it to allocate a

We're abusing the current ASCII driver by telling it to allocate a
9999-line, 9999-character page in the tests.  This causes some systems
to curl up and die because it allocates 20 MB of contiguous RAM.  This
change alleviates at least part of the problem.  It is mostly a
stop-gap until the new output system is ready.

Also, get rid of unused matrix.[ch].