SSPI related code: Unicode support for WinCE

SSPI related code now compiles with ANSI and WCHAR versions of security
methods (WinCE requires WCHAR versions of methods).

Pulled UTF8 to WCHAR conversion methods out of idn_win32.c into their own file.

curl_sasl.c - include curl_memory.h to use correct memory functions.

getenv.c and telnet.c - WinCE compatibility fix

With some committer adjustments

lib/telnet.c

@@ -1341,7 +1341,7 @@ static CURLcode telnet_do(struct connectdata *conn, bool *done)
 
   /* OK, so we have WinSock 2.0.  We need to dynamically */
   /* load ws2_32.dll and get the function pointers we need. */
-  wsock2 = LoadLibrary("WS2_32.DLL");
+  wsock2 = LoadLibrary(TEXT("WS2_32.DLL"));
   if(wsock2 == NULL) {
     failf(data,"failed to load WS2_32.DLL (%d)", ERRNO);
     return CURLE_FAILED_INIT;