Added new files to MANIFEST.

Added new files to MANIFEST.

Started updating tests to use Test::More, rather than the homegrown
print stuff I'd started with (bad darren!).

The load test uses SQL::Translator::load, to both exercise load() and
to perform the actual test (I've intentionally used load instead of
Test::More::use_ok).

Added more dependencies to Makefile.PL.

Sorted the dependencies in PREREQ_PM, and the file list in MANIFEST,
because I'm obsessive about those sorts of silly things.