Fix: Make osmclient Python 3 compatible.

The Python 3 compatibility of osmclient was
completely broken, e.g., print statements without ().
This fixes are mostly done with the automated 2to3
conversion tool.
Some fixes (mixed tabs and spaces) were fixed by hand.

Change-Id: Idea46a4b07e55eaa5bcf5defff64af3f751d740f
Signed-off-by: peusterm <manuel.peuster@upb.de>