====== getServerDateString ======
  * Parameters and types: None
  * Return value and type:
     * code: numberSuccess (ErrorCode.OK) ErrorCode
     * timestr: stringtime description
  * The main function of this method: Get the complete server time
  * The specific use cases are as follows:

<code>
local code, timestr = World:getServerDateString()
if code == ErrorCode.OK then
print('Execution successful', code, timestr )
else
print('Execution failed')
end
</code>