Add cuboids with D <> H, plus regression tests.

Every kind of 1-D, 2-D, and 3-D shape should now be 100% supported.

The Perl script "make-regressions.pl" generates a regression test
for each line in "analog-punct.hpp", by removing the line and seeing
which cuboid from "test.cc" causes the first compiler error. A
complete set of regression tests has been precomputed into the
file "regressions.h", which is #included at the top of each
autogenerated "test.cc".

Generating new tests from scratch is slow and painful (and you must
manually alternate runs of make-regressions.pl with autotest >test.cc).
Setting "my $trust = 1;" will cause the Perl script to trust the
contents of the existing "regressions.h": If a declaration for r42
exists in that file, then we'll assume it's a valid test for line 42.