added enum of layers in preparation for more modular implementation of static effects

src/magic/model/MagicLayer.java

@@ -0,0 +1,20 @@
+package magic.model; 
+
+public enum MagicLayer {
+    Layer1,  //copy 
+    Layer2,  //control changing
+    Layer3,  //text changing
+    Layer4a, //CDA: subtype
+    Layer4,  //type-changing (include sub and super types)
+    Layer5a, //CDA: color
+    Layer5,  //color changing
+    Layer6,  //ability adding/removing
+    Layer7a, //CDA: p/t
+    Layer7b, //set p/t to specific value
+    Layer7c, //modify p/t
+    Layer7d, //p/t changes due to counters
+    Layer7e, //switch p/t 
+    Layer8,  //affect player, not objects
+    Layer9,  //affect game rules, not objects
+    ;
+}