remove leading zeros of enum Number types

[thorsten-wolf-neptune]

hi all, first of all i want to say that i LOVE this framework!!!! Now my suggestion: we have to deal with some strange openapi specs that have enum values as a number that contain leading zeros. To make the endresult more resilliant for these strange definitions i suggest to stripe away leading zeros for number enum values. That's a very simple change but it helps for "strange" open api specs. Also added a test for it that doesn't break anything.