Fix memory leak in 'wrap_index_entry' (issue #18)

pygit2.c

@@ -1655,7 +1655,6 @@ wrap_index_entry(git_index_entry *entry, Index *index) {
 
     py_entry->entry = entry;
 
-    Py_INCREF(py_entry);
     return (PyObject*)py_entry;
 }
 

test/test_leak.py

@@ -1,17 +0,0 @@
-import unittest
-
-import utils
-
-class TestLeak(utils.RepoTestCase):
-    def test_index_iter(self):
-        index = self.repo.index
-        while True:
-            list(index)
-
-    def test_index_getitem(self):
-        index = self.repo.index
-        while True:
-            index[0]
-
-if __name__ == '__main__':
-    unittest.main()