Bug#939930: -doc package should recommend the python3 package

[Matthias Klose]

Package: src:python-lockfile
Version: 1:0.12.2-2
Tags: patch

The -doc package should recommend the python3 package. patch at

http://launchpadlibrarian.net/441479258/python-lockfile_1%3A0.12.2-2_1%3A0.12.2-2ubuntu1.diff.gz