Update tests

Now use unittest for better error indication. This will effectively show where the lists differ instead of just throwing an "AssertError" and also only requires to read the file only once.
In that process also update to Python 3.3.

.travis.yml

 language: python
 python:
-  - "2.7"
+  - "3.3"
 #command to run tests
 script: nosetests

tests/test.py

 import json
+import unittest
 from collections import OrderedDict
 
-def test_json_is_valid():
-	fp = open("repositories.json")
-	json.load(fp)
+# Only run these using `notetests` (or `python -m unittest`) from the root directory
 
-def test_repositories_in_order():
-	j = json.load(open("repositories.json"))
-	repos = j['repositories'][3:]
-	assert repos == sorted(repos, key=unicode.lower)
 
-def test_package_names_in_order():
-	j = json.load(open("repositories.json"), object_pairs_hook=OrderedDict)
-	packages = j['package_name_map'].keys()
-	assert packages == sorted(packages, key=unicode.lower)
+# No need to check for this because all the other tests would fail anyway
+# class TestValidity(unittest.TestCase):
+#     def test_json_is_valid(self):
+#         fp = open("repositories.json")
+#         json.load(fp)
 
-def test_renamed_packages_in_order():
-	j = json.load(open("repositories.json"), object_pairs_hook=OrderedDict)
-	packages = j['renamed_packages'].keys()
-	assert packages == sorted(packages, key=unicode.lower)
+
+class TestOrder(unittest.TestCase):
+    # Do not limit the list comparison to 600 chars (for more detailed debugging)
+    maxDiff = None
+
+    def setUp(self):
+        self.j = json.load(open("repositories.json"), object_pairs_hook=OrderedDict)
+
+    def test_repositories_in_order(self):
+        repos = self.j['repositories']
+        # Remove "https://github.com/SublimeText" at the top because it is purposely not in order
+        del repos[0]
+        self.assertEqual(repos, sorted(repos, key=str.lower))
+
+    def test_package_names_in_order(self):
+        map_packages = list(self.j['package_name_map'].keys())
+        self.assertEqual(map_packages, sorted(map_packages, key=str.lower))
+
+    def test_renamed_packages_in_order(self):
+        ren_packages = list(self.j['renamed_packages'].keys())
+        self.assertEqual(ren_packages, sorted(ren_packages, key=str.lower))