Arithmetic calculation returns an integer format, which should be in double

[daeisbae]

Problem

• Arithmetic calculation like 1 / 2 should return 0.5 But it returns 0 as the return value is rounded (math.floor) due to integer return form

./AParser
>>> 1 / -2     
0
>>> 1 / 2
0
>>> 1 / 3
0
>>> 3 / 5
0
>>> 5 / 3
1

[daeisbae]

Issue solved. Further issue goes to #92