Login Server 1.6.4 config

Configuration for Login Server 1.6.4 release. This purely additive configuration change can be launched before the upcoming code release (separate PR to come.)

Also contains fixes for the following production bugs:
[cfid-1572] Pivotal Network tile links to network.run.pivotal.io instead of network.gopivotal.com  https://www.pivotaltracker.com/story/show/71903846
[cfid-1173] Update tabasco / a1 / prod to configure an smtp server for the login job  https://www.pivotaltracker.com/story/show/69940642