Go get ellipsis (#1)

* gi: rename gi_c into _gi_c

* gi: rename test into _test

* gi: fix README syntax

_test/math0.go

@@ -0,0 +1,13 @@
+package main
+
+import (
+	"fmt"
+	"math"
+)
+
+func main() {
+	fmt.Println(math.Cos(math.Pi))
+}
+
+// Output:
+// -1