Remove CanonicalizeOnCreate, which has never affected behavior

When 056e8ded added RT::User->CanonicalizeUserInfo , it added a
$CanonicalizeOnCreate configuration variable, which nominally controlled
if the method was called.  However, the code was always called, and the
configuration variable was never checked.

Remove the unused configuration variable.
Sphinx 1.10 and above want an explicit binlog_path

Not explicitly setting binlog_path causes it to fall back to the
compiled-in default (often the current directory), which may cause
searchd to not start:

    http://sphinxsearch.com/docs/current.html#conf-binlog-path

Add an explicit binlog_path, accompanied by a comment that is is only
valid on 1.10 and above, as some distributions only ship 0.9.8.
Revert "Sphinx 1.10 and above want an explicit binlog_path"

This reverts commit 79ee4992c229bbe3fb9638fb1128c610a4ed7bcc.  It causes
test failures on installs with sphinx < 1.10.