rstrip null zero from .list lines

[yakra]

This allows traveler lowenbrau to be properly credited for ON405.
As noted in #41 (comment):

Re .list files:
https://github.com/TravelMapping/UserData/blob/9ab420d7cc23d79b6d24f224c7186c88ee6ef777/list_files/lowenbrau.list

The final line, ON ON405 ON/USA PorRd, is followed by 1486 null \0s, before a final CRLF.

We can see that this line is not parsed:
http://travelmapping.net/logs/users/lowenbrau.log
http://travelmapping.net/hb/index.php?units=miles&u=lowenbrau&r=on.on405

This yields the same Python-to-Python diff as the Python-to-C++ diff pasted at #41 (comment)