add cJSON, update mosquitto to 1.6.3 and update the makefile

Guo Wenxue

2019-06-24 809c78de808ed5563e9af4a56227965974ec25fa

 modules/python/sht20.py

old mode 100644
new mode 100755
@@ -1,4 +1,6 @@
#!/usr/bin/python
#-*- coding: utf-8 -*-

import fcntl
import time
import unittest