samples: add Terra samples

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

samples/Terra/quote7.t

@@ -0,0 +1,23 @@
+a = {}
+
+local c = terralib.includec("stdio.h")
+
+
+a.c = quote
+    c.printf("hello\n")
+end
+
+a.b = quote
+    var d = 4
+    a.c
+    return d
+end
+
+
+terra foo()
+    a.c
+    a.b
+end
+
+local test = require("test")
+test.eq(foo(),4)