adding __str__ for kat object which just prints kat script

pykat/finesse.py

@@ -932,6 +932,9 @@ class kat(object):
         
         del self.__blocks[name]
     
+    def __str__(self):
+         return "".join(self.generateKatScript())
+         
     def parseCommands(self, commands, blocks=None, addToBlock=None):
         try:
             if addToBlock is not None and blocks is not None: