Introduce KAnnotatedElement and val annotations: List<Annotation>

compiler/testData/codegen/boxWithStdlib/reflection/annotations/propertyAccessors.kt

@@ -0,0 +1,15 @@
+annotation class Get
+annotation class Set
+annotation class SetParam
+
+var foo: String
+    @Get get() = ""
+    @Set set(@SetParam value) {}
+
+fun box(): String {
+    assert(::foo.getter.annotations.single() is Get)
+    assert(::foo.setter.annotations.single() is Set)
+    assert(::foo.setter.parameters.single().annotations.single() is SetParam)
+
+    return "OK"
+}