allow keywords to change name

db.py

@@ -182,14 +182,17 @@ class db():
             return False
 
     def update_keyword(self, kw):
-        if 'keyword' not in kw or 'weight' not in kw:
+        if 'oldkw' not in kw or 'weight' not in kw or 'newkw' not in kw:
             return False
 
         if not isinstance(kw['weight'], int):
             return False
+
         kwdb = self.c_kw
         try:
-            kwdb.update({'keyword': kw['keyword']}, {'$set': kw})
+            kwdb.update({'keyword': kw['oldkw']},
+                        {'$set':
+                            {'weight': kw['weight'], 'keyword': kw['newkw']}})
             return True
         except Exception:
             print("Dup KW")