helper module _ssl.

The support for the RAND_* APIs in _ssl is now only enabled
for OpenSSL 0.9.5 and up since they were added in that
release.

Note that socketmodule.* should really be renamed to _socket.* --
unfortunately, this seems to lose the CVS history of the file.

Please review and test... I was only able to test the header file
chaos in socketmodule.c/h on Linux. The test run through fine
and compiles don't give errors or warnings.

WARNING: This patch does *not* include changes to the various
non-Unix build process files.