Large integer gets silently altered due to JavaScript number precision limits

[jiz4oh]

When processing JSON containing very large integers, fixjson silently alters the value due to JavaScript's Number precision limitations.

> echo "{'id': 3791411052119578828}" | fixjson

Actual output:

{
  "id": 3791411052119578600
}

Expected output:

{
  "id": 3791411052119578828
}