Add regression tests

Author: nicolasstucki

tests/run/quote-simple-hole.scala

@@ -3,8 +3,12 @@ object Test {
     val x = '{0}
     val y = '{$x}
     val z = '{${'{$y}}}
+    val a = '{{{$x}}}
+    val b = '{{${{'{{$y}}}}}}
     assert(x eq y)
     assert(x eq z)
+    assert(x eq a)
+    assert(x eq b)
 
     val i = '[Int]
     val j = '[$i]