Commented out fixaccounts (not used anywhere). Also improved getnextacctno.

Commented out fixaccounts (not used anywhere). Also improved getnextacctno.

You can test getnextacctno like:
	perl -e 'use C4::Accounts; print getnextacctno(33), "\n";'
where 33 is a borrowernumber out of the accountlines table.  Get that number like:
	mysql> select borrowernumber,accountno from accountlines LIMIT 100;

Signed-off-by: Joshua Ferraro <jmf@liblime.com>