Add regression tests for jot(1).

Adapted from FreeBSD's test suite by attila () stalphonsos ! com.

Minor tweaks:
* make tests work properly with 'make obj' and setting VERBOSE
* add 10 tests checking some examples in our man page
* disable the dddd test for now since it loops forever

Besides dddd, the following five tests fail: dhhd dhhd2 wp3 wp4 wp5
Suggested fixes for these are on tech@

Many thanks to attila for doing the hard work!