Preparing for axTLS. Actual SSL API functions are only stubbed.

Added axTLS to autotool files and glue code to misc other files.
axtls.h maps SSL API functions, but may change.
axtls.c is just a stub file and will definitely change.

lib/urldata.h

@@ -120,6 +120,10 @@
 #include <qsossl.h>
 #endif
 
+#ifdef USE_AXTLS
+#include <axTLS/ssl.h>
+#endif /* USE_AXTLS */
+
 #ifdef HAVE_NETINET_IN_H
 #include <netinet/in.h>
 #endif
@@ -268,6 +272,10 @@ struct ssl_connect_data {
 #ifdef USE_QSOSSL
   SSLHandle *handle;
 #endif /* USE_QSOSSL */
+#ifdef USE_AXTLS
+  SSL_CTX* ssl_ctx;
+  SSL*     ssl;
+#endif /* USE_AXTLS */
 };
 
 struct ssl_config_data {