samples: add Terra samples

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

samples/Terra/class3.t

@@ -0,0 +1,36 @@
+
+C = terralib.includec("stdio.h")
+
+local Class = require("lib/javalike")
+
+
+local Prints = Class.interface { print = {} -> {} }
+
+struct Leaf {
+  data : int
+}
+Class.implements(Leaf,Prints)
+
+terra Leaf:print() : {} 
+  C.printf("%d\n",self.data) 
+end
+
+
+struct Node {
+  next : &Leaf
+}
+Class.extends(Node,Leaf)
+
+terra Node:print() : {} 
+  C.printf("%d\n",self.data) 
+  self.next:print()
+end
+
+terra test()
+  var a,b = Leaf.alloc(), Node.alloc()
+  a.data,b.data,b.next = 1,2,a
+  var p : &Prints = b
+  p:print()
+end
+
+test()