Merge pull request #145 from ricemery/config

add zipper and change to exercises list. Refs #125

Author: ricemery

config.json

@@ -404,6 +404,12 @@
       "topics": [
       ]
 		},
+    {
+      "slug": "change",
+      "difficulty": 1,
+      "topics": [
+      ]
+		},
     {
       "slug": "connect",
       "difficulty": 1,
@@ -422,6 +428,12 @@
       "topics": [
       ]
 		},
+    {
+      "slug": "zipper",
+      "difficulty": 1,
+      "topics": [
+      ]
+		},
     {
       "slug": "forth",
       "difficulty": 1,