replace sys.maxint by sys.maxsize to maintain compatability with Python 3
replace sys.maxint by sys.maxsize to maintain compatability with Python 3

aichaos/rivescript-python,Dinh-Hung-Tu/rivescript-python,aichaos/rivescript-python,Dinh-Hung-Tu/rivescript-python,aichaos/rivescript-python,Dinh-Hung-Tu/rivescript-python