Bad `all_hits` overlap result

Somehow, when the coordinates are big enough, `all_hits` produce wrong results:
```python
bt1 = pybedtools.BedTool("chr1 50000001 50000002", from_string=True)
print(bt1.all_hits(pybedtools.Interval("chr1", 50000000, 50000001), overlap=1.0))
```
produces:
```
[Interval(chr1:50000001-50000002)]
```