Rectify with changes to blead.

Down to 1 failing existing test: link in htmldir3.t.
Add some debugging code in link resolution subroutine.
Activate stdin code.
Move in 3 test files from last year's work.
Add get() method.
Start to revamp testing.

Only put into t those files in which I have a high
degree of confidence.  Move others temporarily to tmp.
Reformulate 003_generate_pages_cache.t to not depend on IO::CaptureOutput.