Followup changes in JerryScript debugger after #1910.

* Remove 'jerry_debugger_cleaup'. Do it automatically in 'jerry_cleanup'.
* Updated the documentations.
* Updated the NuttX and Artik053 targets.

JerryScript-DCO-1.0-Signed-off-by: László Langó llango.u-szeged@partner.samsung.com

jerry-core/include/jerryscript-debugger.h

@@ -40,6 +40,7 @@ typedef enum
 /**
  * Engine debugger functions.
  */
+void jerry_debugger_init (uint16_t port);
 bool jerry_debugger_is_connected (void);
 void jerry_debugger_stop (void);
 void jerry_debugger_continue (void);
@@ -47,9 +48,6 @@ void jerry_debugger_stop_at_breakpoint (bool enable_stop_at_breakpoint);
 jerry_debugger_wait_and_run_type_t jerry_debugger_wait_and_run_client_source (jerry_value_t *return_value);
 void jerry_debugger_send_output (jerry_char_t buffer[], jerry_size_t str_size, uint8_t type);
 
-void jerry_debugger_init (uint16_t port);
-void jerry_debugger_cleanup (void);
-
 /**
  * @}
  */