Fix search paging

* Don't eagerly `refresh_instances` when only `refresh_stubs` is needed
* Inject `expanded` attribute on options in `option_items` template
  context
Merge remote-tracking branch 'origin/develop' into feature/fix-search-paging
Apply lazy-paging fixes to other multiselect modal
Merge pull request #1700 from reciprocity/feature/fix-search-paging

Fix search paging