Clarify 64 bit python docs
Remove PyWin32 readme link

It goes via an adverts page, and is auto displayed on the downloads page anyway.
Add note about 64-bit ice paths
Hypenate 32/64-bit
Make it clearer that versions apply to precompiled pkgs.
Other minor fixes.
merge develop -D org -I include -E exclude: PR 626 (Add new Squash tutorial and screenshots)
merge develop -D org -I include -E exclude: PR 660 (Update documentation to use Pillow instead of PIL (rebased onto develop))
merge develop -D org -I include -E exclude: PR 663 (Windows 64-bit python 11899 (rebased onto develop))