Update WS2_32.lib

[Etienne]

The current winsock library included in D looks like it is meant to be 
compatible with windows 98. With even windows XP not supported by 
Microsoft anymore, could it be possible to include a newer lib with dmd?

I took the care of creating a compatible definitions file that should 
work with any version of windows supported by microsoft:

http://pastebin.com/fj6fQ1nT

I put it through implib and it linked properly.

This would be a nice step towards adding the proper methods and 
structures in std.c.windows.winsock

Is there a chance to see this in the next release?

Thanks!