Docstring fixes

This changeset resolves all known docstring warnings with page.py,
including pep257, but also line lengths.

Several docstrings where altered so they used similar language
to other docstrings.

@return has been added liberally as often the first line of the
docstring contained detailed return information.

colons added where missing.

Change-Id: I35d28dbd4ad87b50f4e93cf6dc460c0fb59ea57a