Change the default collation from strtoupper to Language::uc, so that non-ascii chara...

Change the default collation from strtoupper to Language::uc, so that non-ascii characters get to play too.

I know the uppercase thing is just a standby until a real collation function is written. However in the
mean time, i think it'd be really weird for a wiki with $wgCapitalLinks = false to suddenly have
[[a]] and [[A]] sort under the same letter in a category page, but [[Ä]] and [[ä]] sort no where
near each other, even though on a capitalized wiki they would be the same page.

See discussion on r69816.

Also fix an issue with maintenance/updateCollation.php, where php thinks
that 'uppercase' == 0 (?!). I don't really know what the deal with that
is, but using a ! instead of == 0 seems to fix it. (Follow-up r69961)