add url_utils to common repo from skia repo

Once gs_utils.py is moved into common, these would be the only files left in https://skia.googlesource.com/skia/+/master/tools/pyutils/ .  So let's just move them all...

BUG=skia:2682
R=borenet@google.com

Review URL: https://codereview.chromium.org/382933002