Insert empty lines after functions and properties (KT-4002)

#KT-4002 Fixed

idea/testData/formatter/EmptyLineBetweenClassAndFunction.kt

@@ -0,0 +1,38 @@
+fun f1() {}
+class C1 {}
+
+// -----
+
+fun f2() {}
+class C2
+
+// -----
+
+fun f3 = 1
+class C3 {}
+
+// -----
+
+fun f4 = 2
+class C4
+
+// -----
+
+class C5 {}
+fun f5() {}
+
+// -----
+
+class C6
+fun f6() {}
+
+// -----
+
+class C7 {}
+fun f7 = 1
+
+// -----
+
+class C8
+fun f8 = 1
+