feat(provider/aws): Functions (listing and searching)

[sidmuls]

Issue: https://github.com/spinnaker/spinnaker/issues/4921Issue
Summary:
Add functions support to Spinnaker UI. This is a net functionality that we've been working on for almost a year to this point. The initial backend work was done like three months back.
From then we've worked on creating the UI components with guidance from the Netflix UX team.

Cloud Provider(s): provider/AWS
Environment:
This worked on user's local environment and also through deploying docker images to kubernetes cluster.

Feature Area: @spinnaker/ui-ux-team
Description:
CRUD functionality for managing lambda functions, With this new we must be able to create, update and delete lambda lambda functions through Spinnaker UI
We must also be able to attach target groups to lambda functions using Spinnaker UI.
Additional Details:
Clouddriver backend details: https://github.com/spinnaker/clouddriver/tree/master/clouddriver-lambda

[spinnakerbot]

The following commits need their title changed:

• c7d0768: .

• d1b43d2: refactor(provider/aws): removing extra line. Tthis is actually for retrying tests on TravisCI

Please format your commit title into the form:

<type>(<scope>): <subject>, e.g. fix(kubernetes): address NPE in status check

This allows us to easily generate changelogs & determine semantic version numbers when cutting releases. You can read more about commit conventions here.

[erikmunson]

pulled this down and ran it locally, feature flagging seems to have fixed the issues with data sources and I'm told by @sidmuls that if the backend has functions turned on the endpoint this code hits will return an empty array, so I'm satisfied. Thanks for adding the flag as requested!