Added login credential information to main README.

Added README for sample_project that also contains login credentials for the impatient.

sample_project/README

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+Thanks for download django-admin-sortable.
+I hope it can help you out as much on your project(s) as it does on mine :)
+
+The only url patterns that are enabled for this project are /admin
+The username/password is: admin/admin
+
+If you still need help, please contact me at: btaylorweb@gmail.com
+
+Kind regards,
+Brandon Taylor
+
+bTaylor Web