JetCompilerMessagingTest and K2JSCompilerMessagingTest: tests that launch the cli compiler and check that resulting messages are in correct format

idea/testData/compilerMessages/k2js/helloWorld/src/test.kt

@@ -0,0 +1,3 @@
+package foo
+
+fun main(args : Array<String>) {}

idea/testData/compilerMessages/k2js/lib/src/test.kt

@@ -0,0 +1,8 @@
+package foo
+
+import js.*
+
+fun main(args : Array<String>) {
+  val c = 4 + libf()
+  c == 2
+}

idea/testData/compilerMessages/k2js/simpleError/src/test.kt

@@ -0,0 +1,5 @@
+package foo
+
+fun f() : Boolean {
+
+}

idea/testData/compilerMessages/k2js/simpleWarning/src/test.kt

@@ -0,0 +1,5 @@
+fun main(args : Array<String>) {
+  val t = 0
+  if (t != null) {
+  }
+}