Check (and correct) access parameters for D6.2

The maintainers newsletter states the following API change in Drupal 6.2:

... main part of the API change consists of requiring an explicit
definition of the access parameters for each menu router item. Access callbacks
and arguments will no longer be inherited by items that might be considered to
be children based on their path. The only exception to this is for items of type
MENU_DEFAULT_LOCAL_TASK. The function user_access() is still the default access
callback, so you may continue to rely upon that being used as the default if you
only define the access arguments. Note that modules that currently rely on
access inheritance WILL NOT work correctly with 6.2.

We will need to check and correct access parameters for gallery menu items.