Enable NPN

Next Protocol Negotiation extension. See https://technotes.googlecode.com/git/nextprotoneg.html
This seems to be fixed now

I was getting an error about duplicate client_max_body_size directive.
Fix JSON parsing error 

‘upstream_response_time: -‘ isn’t handled.
Merge pull request #668 from alphagov/feature/fix-nginx-json-log

Fix JSON parsing error
Configure unattended upgrades appropriately

Take from GOV.UK puppet. Picked up the ITHC that we didn’t appear to be
installing things in the background that we could do.
Merge pull request #663 from alphagov/feature/npn

Enable NPN
Merge pull request #670 from alphagov/feature/unattended-upgrades

Configure unattended upgrades appropriately
WIP: Upgrade sensu and module

Successfully provisioned a monitoring-1 and backup-box-1 with this,
after provisioning with master

sensu-api does not seem to be running, need to find out why

need to use https://github.com/Yelp/puppet-uchiwa to setup a dashboard
as the sensu dashboard has been removed
Add uchiwa puppet module and config

Uchiwa replaces the sensu dashboard
Settings required for latest puppet module

 - Be explicit about the api
 - Need to specify a version of the sensu plugin gem
Fix sensu vhost

The puppet module changed the default vhost to not include a slash -
https://github.com/sensu/sensu-puppet/pull/184

This unfortunately broke our setup, which expected a slash in the vhost.
Change upstream port to uchiwa port

Uchiwa defaults to 3000, so set the nginx upstream to use that