Changes to strings in update-manager

[Josh Holland]

My branch of string fixes for update-manager just got merged, changing a
few user-visible strings. I am posting this to the list because mvo told
me to.

I have attached a diff of my changes, most of which are in docstrings
and comments and the like, but one or two things have changed.
Apparently the new POT file has been uploaded.

Just as a side thing, this is my first accepted contribution to a FOSS
project. It's great to know that every single Ubuntu user will be using
something I helped to write!

-- 
Josh Holland <jrh at joshh.co.uk> (key F6067C12)
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