Prefs rework

Updated preferences to use tabbed interface. Required template changes and css updates
Menu changes to make menus sane after preference updates.
Some other preference related changes as well.

This change needs a database deletion.  There are four items in the menus table for the usres menu.  From /themes/slashcode/sql/mysql/datadump.sql 

#
# Dumping data for table 'menus'
#

INSERT INTO menus (menu, label, sel_label, value, seclev, showanon, menuorder) VALUES ('users','Logout','logout','/my/logout',1,0,10);
INSERT INTO menus (menu, label, sel_label, value, seclev, showanon, menuorder) VALUES ('users','Preferences','preferences','/users.pl?op=edituser',1,0,20);
INSERT INTO menus (menu, label, sel_label, value, seclev, showanon, menuorder) VALUES ('users','Password','password','[% constants.real_rootdir %]/my/password',1,0,40);
INSERT INTO menus (menu, label, sel_label, value, seclev, showanon, menuorder) VALUES ('users','~[% user.nickname | strip_literal %] ([% user.uid %])','me','/~[% user.nickname | fixparam %]',1,0,50);


These values are not needed with this code and should be purged from the database.
This is a sample command:
delete from menus where menu='users';