fix(stream): cast timestamps as ints

[jcderr]

python datetime/time timestamps will sometimes be floats, such as when you do this:

>>> time.mktime(datetime.datetime.now().timetuple())

The HTTP throws non-specified errors when these are passed. Casting them as int() resolves this.

[remh]

Thanks a lot @jcderr !
@yannmh Can you review merge and release when you'll have a chance ?

[yannmh]

Thanks @jcderr ! I am merging your contribution.