Display bookmark name

Have field in struct and display the name in `/bookmark list`.

Regards https://github.com/profanity-im/profanity/issues/697

src/xmpp/xmpp.h

@@ -93,6 +93,7 @@ typedef struct bookmark_t {
     char *barejid;
     char *nick;
     char *password;
+    char *name;
     gboolean autojoin;
 } Bookmark;