Bug#849106: dh_python2 info about dh-python build-dep not in manpage

[Ian Jackson]

Package: python
Version: 2.7.9-1

I saw this message
  W: dh_python2:479: Please add dh-python package to Build-Depends
when my rules file ran (indirectly) dh_python2.

However the FM, dh_python2(1), does not mention putting dh-python in
the Build-Depends.

Ian.