Support 'break' and 'continue' in expressions

- generate fake jump instructions so that we can always analyze stack depths
- fix stack before break and continue by dropping excessive elements (e.g., *a*.foo(*b*, c?:continue))
- Analyzer rewritten in Kotlin, with more flexible control of CFG traversal

 #Fixed KT-3340
 #Fixed KT-4258
 #Fixed KT-7941

compiler/testData/codegen/box/controlStructures/breakContinueInExpressions/innerLoopWithStack.kt

@@ -0,0 +1,9 @@
+fun box(): String {
+    var x = "OK"
+    do {
+        while (true) {
+            x = x + break
+        }
+    } while (false)
+    return x
+}