Aggregate Cloud.gov ES instances

[elipe17]

Description:
As the development of Kibana has wrapped up it has been discovered that it is prohibitelve expensive to deploy ES, Kibana, and the ES proxy on a per app basis. Thus, we want to aggregate all ES instances into one singular (larger) instance to help mitigate cost and deployment complexity.

Acceptance Criteria:
Create a list of functional outcomes that must be achieved to complete this issue

• Singular Elastic instance
• Singular Kibana instance
• Frontend and backend apps for all environments happily talk to the singular instances
• Testing Checklist has been run and all tests pass
• README is updated, if necessary

Tasks:

• Delete existing Elastic instances
• Update Terraform to stand up a singular Elastic instance
• Update deploy scripts to connect frontend/backend apps to the correct Elastic instance
• Update Kibana and Elastic proxy deployment manifests to not be environment specific
• Redeploy/restage frontend/backend apps so that they connect to the new instances

Notes:
Add additional useful information, such as related issues and functionality that isn't covered by this specific issue, and other considerations that will be helpful for anyone reading this

• Note 1
• Note 2
• Note 3

Supporting Documentation:
Please include any relevant log snippets/files/screen shots

• Doc 1
• Doc 2

Open Questions:
Please include any questions or decisions that must be made before beginning work or to confidently call this issue complete

• Open Question 1
• Open Question 2