SSH-AGENT

1. For the client agent command line option, add the flag to the flag string.
2. Update PostSignRequest() to support all flavors of ECDSA and to
   switch out code for missing algorithms.
3. Hide function SendRequestIdentities().

Author: ejohnstown

examples/client/client.c

@@ -826,7 +826,7 @@ THREAD_RETURN WOLFSSH_THREAD client_test(void* args)
     char**  argv = ((func_args*)args)->argv;
     ((func_args*)args)->return_code = 0;
 
-    while ((ch = mygetopt(argc, argv, "?c:eh:i:j:p:tu:xzNP:R")) != -1) {
+    while ((ch = mygetopt(argc, argv, "?ac:eh:i:j:p:tu:xzNP:R")) != -1) {
         switch (ch) {
             case 'h':
                 host = myoptarg;