Fixed HTTPAnswerJSON behaviour when receiving string data

Added DateStrCheckAge, DateStrCheckRange and DateStrCheckErrMessage

Signed-off-by: miguel <[email protected]>

v1.1.16 added test for HTTPAnswerJSON()

Signed-off-by: miguel <[email protected]>

Added HTTPAnswerJSON() to v1.1.4

Signed-off-by: miguel <[email protected]>

updateed README.md

Signed-off-by: miguel <[email protected]>