New tests

- ckannot.ept : bug with clock annotations handling in Normalize (corrected)
- threestates.ept : handling of merges in Normalize (corrected)

test/good/ckannot.ept

@@ -0,0 +1,5 @@
+node f(x:int;c:bool) returns (y:int)
+let
+  y = (x :: .) when c;
+tel
+

test/good/threestates.ept

@@ -0,0 +1,30 @@
+node f(x:int) returns (y:int)
+let
+  automaton
+    state A
+      do
+	y = 1;
+      until (x = 0) then B
+    state B
+      do
+	y = 2;
+      until (x = 1) then C
+    state C
+      do
+	automaton
+	  state D
+	    do
+	      y = 3;
+	    until (x = 2) then E
+	  state E
+	    do
+	      y = 4;
+	    until (x = 3) then F
+	  state F
+	    do
+	      y = 5;
+	    until (x = 4) then D
+	end
+      until (x = 5) then A
+  end
+tel