Allow to specify ordering when retrieving meta data

The query now searches in more fields. For example, when getting a
list of tags, the query is applied to the tag name *and* category.
When listing persons, the query now also looks in the associated
organization name.

This has been used to make some headers in the meta data tables
clickable to sort the list accordingly.

Refs: #965, #538

modules/webapp/src/main/elm/Messages/Comp/FolderTable.elm

@@ -20,6 +20,7 @@ type alias Texts =
     { basics : Messages.Basics.Texts
     , memberCount : String
     , formatDateShort : Int -> String
+    , owner : String
     }
 
 
@@ -28,6 +29,7 @@ gb =
     { basics = Messages.Basics.gb
     , memberCount = "#Member"
     , formatDateShort = DF.formatDateShort Messages.UiLanguage.English
+    , owner = "Owner"
     }
 
 
@@ -36,4 +38,5 @@ de =
     { basics = Messages.Basics.de
     , memberCount = "#Mitglieder"
     , formatDateShort = DF.formatDateShort Messages.UiLanguage.German
+    , owner = "Besitzer"
     }