Added untested DNS client code

include/libzt.h

@@ -413,6 +413,15 @@ int zts_gethostname(char *name, size_t len);
  */
 int zts_sethostname(const char *name, size_t len);
 
+/**
+ * @brief Return a pointer to an object with the following structure describing an internet host referenced by name
+ *
+ * @usage Call this after zts_start() has succeeded
+ * @param name
+ * @return Returns pointer to hostent structure otherwise NULL if failure
+ */
+struct hostent *zts_gethostbyname(const char *name);
+
 /**
  * @brief Close a socket
  *