allow to copy and paste rightsset from zenphoto lib-auth.php, refactor numeric rights calculation

this is take one. TODO: use numeric rights for the values of the multichoice and translate or find a way to store $rightsset in only one place
write passhash-value in database, whitespace stuff
update cookie contents to current zenphoto version
update cookie contents to current zenphoto version
add option to choose which password hash mechanism to choose instead of defaulting to md5
use prepared statements, update passhash parameter too on updating users password details
update cookie contents to current zenphoto version
put rightsset in just one place
add 'ignored users' config variable
rebrand to be in accordance with GPLv3