Fixes for building on MSVC #1649
Note that postfixes on the binaries are required if you use MSVC to "install" it to a folder.
The headers are all identical, but the binaries differ (of course).
FWIW pycurl windows build process goes through some effort to get libcurl and all of its dependencies linked to the same & correct msvcrt (which in turn is dictated by python).
For example, even though pycurl links in libcurl, zlib, openssl etc. statically, all of them are built to reference msvcrt dll as that's what python uses.