Further categorylinks schema changes

Further categorylinks schema changes

Per review by Tim, I made two changes:

1) Fix cl_sortkey to be varbinary(255).

2) Expand cl_collation to varbinary(32), and change $wgCollationVersion
to $wgCategoryCollation, to account for the variety of collations we
might have.  tinyint is too small.  I could have gone with int, but
that's annoyingly inscrutable in practice, as we all know from namespace
fields.

To make the upgrade easier for non-trunk users, I updated the old patch
file to incorporate the new changes, using the updatelog table so that
people upgrading from 1.16 won't have to do two alters on categorylinks.
I didn't test the upgrade-from-1.16 code path yet, so if anyone tests
that and it seems not to break, commenting to that effect would be
appreciated.

Also removed wfDeprecated() from archive().  Do *not* add this to
functions that are still actively used in core.  If you think this
function is so terrible that it really mustn't be used, remove callers
yourself, don't pester every single developer with messages in the hope
that someone else will do it for you.