Capitalized include headers (Winsock2.h and Ws2tcpip.h) in tests/test_srcfd.cpp

[ragnarruutel]

Windows wont care but building under linux with mingw-w64 will fail since the header filenames are all in lowercase letters.

Zeromq version: 4.1.0-rc1

tests/test_srcfd.cpp
25,26c25,26
< #include <Winsock2.h>

< #include <Ws2tcpip.h>

include <winsock2.h>

include <ws2tcpip.h>