lynx-dev WIN32 port: makefile.w32 update

[Leonid Pauzner]

Looking into root makefile.w32 I found out
that several recent features not used there as defaults,
at least the following options should be added:

DISP_PARTIAL;SOURCE_CACHE;USE_PSRC

Also LYPrettySrc.[o] should be added to the list of objects.

I have no working win32 compiler environment so cannot do it properly
but the syntax of makefile.w32 seems very obvious to add options
into two places.