Add primitive types to String conversion. (#50)

backend.native/tests/build.gradle

@@ -186,6 +186,12 @@ task hello3(type: RunKonanTest) {
     source = "runtime/basic/hello3.kt"
 } */
 
+
+task tostring0(type: RunKonanTest) {
+    goldValue = "127\n255\n239\nA\n1122334455\n112233445566778899\n1E+27\n1E-300\ntrue\nfalse\n"
+    source = "runtime/basic/tostring0.kt"
+}
+
 task if_else(type: UnitKonanTest) {
     source = "codegen/branching/if_else.kt"
 }

backend.native/tests/runtime/basic/tostring0.kt

@@ -0,0 +1,14 @@
+fun main(args : Array<String>) {
+    println(127.toByte().toString())
+    println(255.toByte().toString())
+    println(239.toShort().toString())
+    println('A'.toString())
+    // println('Ё'.toString())
+    // println('ト'.toString())
+    println(1122334455.toString())
+    println(112233445566778899.toString())
+    println(1e27.toFloat().toString())
+    println(1e-300.toDouble().toString())
+    println(true.toString())
+    println(false.toString())
+}