#15 New command-line 'styles' for services

[Mark Hammond]

This patch offers a new 'cmdline-style' option - the
default 'py2exe' is the same as before, but 'pywin32'
and 'custom' are also available. I've also added a
brief note to py2exe.txt.

Note it also incorporates the patch in "1463044:
Setting a service description with _svc_description_",
so I will close that.

Let me know if you are happy for me to check this in!