Bug 64855 - get.py not ported from compat but added to listpages.py

Optionally, page content is retrieved and written to standard output.
This makes it possible to pipe the text to another process.

Change-Id: Ibd4717af9763d4989e36902b0210f411709f9f48
Merge "Bug 64855 - get.py not ported from compat but added to listpages.py"