Edited Feature: Collections support [2]

type declaration:<br />`Type CollectionOfStrings = System.String[]`<br />usage (see ModularEngine/samples/MultiMain/collections.mdkal):<br />`<br />relation rel(A: CollectionOfStrings)<br /><br />knows rel(["qwe"; "asd"; "zxc"])<br />knows rel([])<br /><br />with A: CollectionOfStrings<br />if rel(A) && asInfon({|"basic"|A.exists("qwe")|})<br />do send to me: rel(A)<br /><br />if rel(A) && asInfon({|"basic"|A.isEmpty()|})<br />do send to me: log("empty") && rel(A)<br />`