Application Lifecycle Management

[benjaminws]

This PR makes it so the application lifecycle can be managed completely. The user can now create an application configuration and then create an application in spinnaker based off of it. Additionally, this allows existing applications to be updated. Lastly, this implements a delete operation for applications, which does as its name suggests.

• Allows applications to be codified
  • This does no validation of the application document
  • Poorly formed configs will fail at the API
• Refactor CreateApplicationJob to be more generic ApplicationJob
• Add example application config
• Implement delete application feature

[benjaminws]

Good feedback, thanks! I fixed that up and took care of the conflicts.