Big change in quickfix tests: no stupid test data format with "before" and "after" file prefixes

idea/testData/quickfix/checkArguments/nonVarargSpread.kt.after

@@ -0,0 +1,12 @@
+// "Remove '*'" "true"
+fun join(x : Int, vararg a : String) : String {
+    val b = StringBuilder(x.toString())
+    for (s in a) {
+        b.append(s)
+    }
+    return b.toString()
+}
+
+fun main(args : Array<String>) {
+    join(<caret>1, "2")
+}