samples: add Terra samples

source: https://github.com/zdevito/terra/tree/master/tests

samples/Terra/terralua.t

@@ -0,0 +1,32 @@
+function dog(...)
+	print("Hi. This is Dog.",...)
+end
+
+terra foo()
+	dog()
+end
+
+terra passanarg()
+	dog(3,4,5,nil)
+end
+
+function takesastruct(a)
+	print(a.a,a.b)
+	a.a = a.a + 1
+end
+struct A { a : int , b : double }
+terra passastruct()
+	var a = A {1,3.4}
+	--takesastruct(a) luajit doesn't like having structs passed to its callbacks by value?
+	var b = a.a
+	takesastruct(&a)
+	var c = a.a
+	return b + c
+end
+
+foo()
+passanarg()
+
+local test = require("test")
+
+test.eq(passastruct(),3)