String addition in mutter

[Didier Roche]

Hey fellow translators.

It seems that a lot of people are encountering this bug:
https://bugs.launchpad.net/ubuntu-translations/+bug/651085.

Which means, they don't know what to do when the previous message tell
them that they can't log into the Ubuntu Netbook Edition session (as
there is no 3D support).

After discussing with dpm, the only solution at this stage of the cycle
is to add an additional message. I've tricked gettext so that you don't
have to retranslate for those who had) the previous dialog. It's just
adding a carriage return to the dialog box and this string: "If you are
on Ubuntu live CD, the username is \"ubuntu\" and you have to enter a
blank password." (forget the \n I added to the bug report comment).

I'm really really sorry for the late notice of that. Please keep in mind
that's the current situation is already better than what we had one week
before (stuck in a session where mutter/unity is respawning), so I don't
think it's that important if it's not translated (in other words not too
much pressure there).

Please, keep in mind that's in the mutter package, not unity one :)

Thanks again everyone and sorry for that!

Cheers,
Didier