Computation may be wrong in python 3

[cslashm]

here:
https://github.com/warner/python-ecdsa/blob/fa18c32f4b6cf80c763f8968ed7c48706922e226/src/ecdsa/rfc6979.py#L56

The line should be change in rolen = int((qlen + 7) / 8)

Indeed in python3 / always return a float, then line 96 the comparison
len(t) < rolen may lead into some aberration such as 32<32 that return True.

This is because of float encoding.

[tomato42]

ok, #194 should fix it

[cslashm]

yes :). I didn't remember // was python2 ok.