tries to read *.pth files on interpreter startup.

regression tests in parallel, shortening the total runtime.

the various profiling modules (profile, cProfile). Patch by Hagen Fürstenau.

command name even when executable is specified.

-Wall -Wstrict-prototypes -Werror" in both --with-pydebug mode and --without.
There's still a batch of non-prototype warnings in Xlib.h that I don't know how
to fix.

function.