Update win32 build instructions

Cosmetic changes to the build instructions for windows users.

I didn't have to build library dependencies since I downloaded the
prebuild 64 bit dependency package.
Update win32 instructions

Fixed a typo
Merge pull request #749 from sidhujag/master

Win32 build instructions update
Merge branch 'master' of https://github.com/bitshares/bitshares_toolkit