Updating changelog and revision number

Author: pavanky

CHANGELOG.md

@@ -1,3 +1,6 @@
+### v3.5.20170721
+- Bug fixes for canny edge detection
+
 ### v3.5.20170718
 - Feature parity with ArrayFire 3.5.
     - `canny`: Canny Edge detector

setup.py

@@ -19,7 +19,7 @@
     author="Pavan Yalamanchili",
     author_email="contact@pavanky.com",
     name="arrayfire",
-    version="3.5.20170718",
+    version="3.5.20170721",
     description="Python bindings for ArrayFire",
     license="BSD",
     url="http://arrayfire.com",