Add deployment ids to app locked error message

- Fixes #450
Merge pull request #453 from mesosphere/issue-450-app-locked-message

Add deployment ids to app locked error message
DELETE on a nonexistent app should return 404

- Fixes #451
Merge pull request #454 from mesosphere/issue-451-delete-404

DELETE on a nonexistent app should return 404
Enhanced app locked error message.
Enhanced app locked error message.
Enhancement 436

Determines whether URI should be extracted or not and updates the URI
with the appropriate extract flag.
Merge pull request #455 from elingg/master

Enhancement 436
Support for new ContainerInfo message in Mesos
Updated Mesos dependency to master snapshot
Merge pull request #439 from mesosphere/dockerinfo

Consistency with upcoming docker support in Mesos
App deletion defaults to force=true.
Default number of app instances = 1
GET /v2/apps/some/app now lists active deployments
Merge pull request #457 from mesosphere/issue-452-list-app-deployments

GET /v2/apps/some/app now lists active deployments
Update Docker.json
Store groups before initiating a deploy.
fix app ids on update
Persist apps before deploying them so that they can show up in the UI
Merge pull request #459 from olix0r/issue-458

Issue 458 -- Store groups & apps before executing updates