commands() - returns some information about actions the user can take
Returns an array of an array of 4 items describing the actions that are
available to this_object(). The first item is the command itself (as
passed to add_action()). The second is the set of flags (passed to
add_action as the third argument, often defaulted to 0). The third is
the object that defined the action. The fourth is the function to be
called ("<function>" if it is a function pointer).
add_action(3), enable_commands(3), disable_commands(3)