Update the Tomcat Access Log Pattern

Due to a change in the Access Logging produced by the GoRouter the
'X-Forwarded-For' header is no longer required. The commit removes it.

See: https://github.com/cloudfoundry/java-buildpack/issues/75#issuecomment-53535349

[#77701034]
Merge branch 'cgfrost-77701034-Access-Logs-Headers'

[resolves #75]
Merge remote-tracking branch 'upstream/master'