dictresize() was too aggressive about never ever resizing small dicts.
If a small dict is entirely full, it needs to rebuild it despite that
it won't actually resize it, in order to purge old dummy entries thus
creating at least one virgin slot (lookdict assumes at least one such
exists).

Also took the opportunity to add some high-level comments to dictresize.

tuples by filename/lineno, then sort the catalog entries by their
location tuples.

tabs.  The title was centered using 8-byte tabs, however, and the
result looked strange.  Fixed this.

Change test_doctest and test_difflib to pass regrtest's notion of
verbosity on to doctest.
Add explanation for a dozen "new" things to test/README.

testing using doctest and PyUnit.

generating it.  Since this is purely a doctest, the output file never
served a good purpose.

Fixed glue initialization code so prototype is correct.

tests were moved to PyUnit.

Message object.

Lots more Carbon/Carbon.h includes, new UPP routine names, function prototypes. Most toolbox modules now compile, link and import in MacOSX-MachO python.

for this.

The idea is Marc-Andre Lemburg's, the implementation is Tim's.
Add a new ma_smalltable member to dictobjects, an embedded vector of
MINSIZE (8) dictentry structs.  Short course is that this lets us avoid
additional malloc(s) for dicts with no more than 5 entries.

The changes are widespread but mostly small.

Long course:  WRT speed, all scalar operations (getitem, setitem, delitem)
on non-empty dicts benefit from no longer needing NULL-pointer checks
(ma_table is never NULL anymore).  Bulk operations (copy, update, resize,
clearing slots during dealloc) benefit in some cases from now looping
on the ma_fill count rather than on ma_size, but that was an unexpected
benefit:  the original reason to loop on ma_fill was to let bulk
operations on empty dicts end quickly (since the NULL-pointer checks
went away, empty dicts aren't special-cased any more).

Special considerations:

For dicts that remain empty, this change is a lose on two counts:
the dict object contains 8 new dictentry slots now that weren't
needed before, and dict object creation also spends time memset'ing
these doomed-to-be-unsused slots to NULLs.

For dicts with one or two entries that never get larger than 2, it's
a mix:  a malloc()/free() pair is no longer needed, and the 2-entry case
gets to use 8 slots (instead of 4) thus decreasing the chance of
collision.  Against that, dict object creation spends time memset'ing
4 slots that aren't strictly needed in this case.

For dicts with 3 through 5 entries that never get larger than 5, it's a
pure win:  the dict is created with all the space they need, and they
never need to resize.  Before they suffered two malloc()/free() calls,
plus 1 dict resize, to get enough space.  In addition, the 8-slot
table they ended with consumed more memory overall, because of the
hidden overhead due to the additional malloc.

For dicts with 6 or more entries, the ma_smalltable member is wasted
space, but then these are large(r) dicts so 8 slots more or less doesn't
make much difference.  They still benefit all the time from removing
ubiquitous dynamic null-pointer checks, and get a small benefit (but
relatively smaller the larger the dict) from not having to do two
mallocs, two frees, and a resize on the way *to* getting their sixth
entry.

All in all it appears a small but definite general win, with larger
benefits in specific cases.  It's especially nice that it allowed to
get rid of several branches, gotos and labels, and overall made the
code smaller.

isabs() (no false results were checked) and splitdrive().

Update to reflect using "" as the default value for the second parameter
to the get() method.

setdefault() the empty string.  In setdefault(), use + to join the value
to create the entry for the headers attribute so that TypeError is raised
if the value is of the wrong type.

When regrtest.py finds an attribute "test_main" in a test it imports,
regrtest runs the test's test_main after the import.  test_threaded_import
needs this else the cross-thread import lock prevents it from making
progress.  Other tests can use this hack too, but I doubt it will ever be
popular.

This should be faster.

This means:

(1) "for line in file:" won't work if the xreadlines module can't be
    imported.

(2) The body of "for line in file:" shouldn't use the file directly;
    the effects (e.g. of file.readline(), file.seek() or even
    file.tell()) would be undefined because of the buffering that goes
    on in the xreadlines module.

ought to be faster.

instead.  Allows this test to finish on Windows again.

localization of month and day names.

when #ifdef was needed.

This closes (reallu!) SF bug #417418.

add a list of the mapping methods which are not supported (per Barry's
comments).

objects.