#2 Warn about windows-1252 presented as ISO-8859-1

[Joseph Walton]

It's fairly common to find Windows-encoded XML declared
as ISO-8859-1; this causes problems for any strict
parser, as smart-quotes (and a few other characters)
turn out as undefined characters.

This patch adds a warning when these characters show
up; if people have taken the time to use a validator,
it's good to make them aware of this kind of edge-case.

[Joseph Walton]

Patch to warn about illegal characters

[Sam Ruby]

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Patch applied! Thanks!

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make sure that a new file is created in
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