[cfid-1173] Update tabasco / a1 / prod to configure an smtp server for the login job
- Add SMTP server config properties to the spec and login.yml.erb so they will be passed to login.yml by bosh

[#69940642] https://www.pivotaltracker.com/story/show/69940642
[cfid-1572] Pivotal Network tile links to network.run.pivotal.io instead of network.gopivotal.com
- Replace erroneous default Pivotal Network links with nils in open source config

[#71903846] https://www.pivotaltracker.com/story/show/71903846
[cfid-1554] Add new tile to pivotal branded landing page
- Add tiles placeholder to spec and cf-properties
- Add parsing of list of tile hashes to login.yml.erb
TODO: Add tiles config to environment stubs

[#71802710] https://www.pivotaltracker.com/story/show/71802710
Use nil for default tiles config instead of explicit merge.
- Makes config optional

[#71802710] https://www.pivotaltracker.com/story/show/71802710
Update to latest ruby patch version.
Merge remote-tracking branch 'origin/pr/413' into develop

Signed-off-by: Matthew Sykes <matthew.sykes@gmail.com>