cli: Added a welcome and help message

When gluster command is fired without any arguments it just shows the
prompt, so added a welcome message and info to get help.

fixes: bz#1535528

Change-Id: I627b66b67443716e9270025c1e47b98b6facba13
Signed-off-by: Rinku Kothiya <rkothiya@redhat.com>

cli/src/cli-rl.c

@@ -346,6 +346,9 @@ cli_rl_input(void *_data)
 
     state = _data;
 
+    fprintf(stderr,
+            "Welcome to gluster prompt, type 'help' to see the available "
+            "commands.\n");
     for (;;) {
         line = readline(state->prompt);
         if (!line)

cli/src/input.c

@@ -45,6 +45,9 @@ cli_input(void *d)
 
     state = d;
 
+    fprintf(stderr,
+            "Welcome to gluster prompt, type 'help' to see the available "
+            "commands.\n");
     for (;;) {
         printf("%s", state->prompt);