include "any" option when schema allows it
separate testcase for any option
add groupers to facets relations
add dropdown_with_groups template
set display_in_groups=true if conditions are met
use dropdown_with_groups for SelectFilter
exclude "any" from options requests args
use group labels for optgroups
datapoints request refactoring
omit "any" from args when requesting datapoints
minor fixes
Merge branch 'any-select'