Enable tests on Visual Studio

- add patch for aeadtest.c to undef IN
- add patch for ocsp_test.c to call BIO_sock_init() before getaddrinfo()
- define STDERR_FILENO in unistd.h to build pkcs7test.c
- add option ENABLE_VSTEST(default OFF) to enable test on Visual Studio
- modify to pass test data file as an argument (aeadtest, evptest)
- add Windows scripts (ocsptest, pq_test, ssltest, testdsa, testenc, testrsa)
- do not build pidwraptest on MSVC
- fix some indentations

include/compat/unistd.h

@@ -14,6 +14,8 @@
 #include <io.h>
 #include <process.h>
 
+#define STDERR_FILENO   2
+
 #define R_OK    4
 #define W_OK    2
 #define X_OK    0