KT-1781 Can't distinguish between two constructors

#KT-1781 Fixed

 Now, if foo() and foo(vararg bar) both match the call site, the first one is preferred

compiler/testData/resolve/varargs/NilaryVsVararg.jet

@@ -0,0 +1,10 @@
+~nilary~fun foo0() : String = "noarg"
+
+~vararg~fun foo0(vararg t : Int) : String = "vararg"
+
+fun test0() {
+    `nilary`foo0()
+    `vararg`foo0(1)
+    val a = intArray()
+    `vararg`foo0(*a)
+}

compiler/testData/resolve/varargs/UnaryVsVararg.jet

@@ -0,0 +1,10 @@
+~unary~fun foo1(a : Int) : String = "noarg"
+
+~vararg~fun foo1(a : Int, vararg t : Int) : String = "vararg"
+
+fun test1() {
+    `unary`foo1(1)
+    `vararg`foo1(1, 1)
+    val a = intArray()
+    `vararg`foo1(1, *a)
+}