Add enumeration support. (#128)

* Add enumeration support.

* Enum classes lowering.

* merge fix

* merge fix

* used arrayOf from irModule

* changed lowering quant from body to file

* refactoring

* review fixes

* lowering for GET_OBJECT in enums

* enabled tests

* added tests

* moved tests to separate dir

* renamed test files

* moved phase up

* review fixes

* reformat

backend.native/tests/external/codegen/blackbox/enum/emptyConstructor.kt

@@ -1,5 +1,5 @@
 // TODO: muted automatically, investigate should it be ran for JS or not
-// IGNORE_BACKEND: JS, NATIVE
+// IGNORE_BACKEND: JS
 
 package test
 

backend.native/tests/external/codegen/blackbox/enum/kt9711_2.kt

@@ -1,5 +1,5 @@
 // TODO: muted automatically, investigate should it be ran for JS or not
-// IGNORE_BACKEND: JS, NATIVE
+// IGNORE_BACKEND: JS
 
 enum class IssueState {