Keystone access log in key-access screen

When Keystone was run in Apache Httpd the access log wasn't in a
screen. A new screen called key-access is now started with
Keystone's access log.

Change-Id: Ie1f4d4b679e1b9c87f0cea37deb25f7b6636fe01
Closes-Bug: #1359995
Merge "Keystone access log in key-access screen"