feature suggestion - web frontend group subselects

[richlv]

create a group, add two hosts to the group.
add a trigger to each of them.
in trigger section, attempt to view all triggers for a group.
this is impossible, as subselect has no 'all hosts' entry.

it would b nice if subselect had 'all hosts' entry even when a group is selected (this applies to several places, including triggers, graphs, vents and probably others)