CLI tests: add LauncherScriptTest instead of generated 'kotlinc' script tests

The compiler behavior on test data in compiler/testData/cli is already tested
with CliTestGenerated, which is 4x faster and does not require to rebuild the
compiler jar with 'ant dist'. Leave only several simple tests to check that
'kotlinc', 'kotlinc-jvm' and 'kotlinc-js' scripts work

compiler/testData/launcher/emptyMain.kt

@@ -0,0 +1,4 @@
+package test
+
+fun main(args: Array<String>) {
+}

compiler/testData/launcher/helloWorld.kt

@@ -0,0 +1,5 @@
+package test
+
+fun main(args: Array<String>) {
+    println("Hello!")
+}