Asynchronous updates from API server

[bodom0015]

Currently, when performing a start/stop the "Auto Refresh" functionality is enabled. This simply performs a GET on the following 2 URLs every 1-2 seconds:

• /projects/{project-id}/stacks
• /projects/{project-id}/volumes

While this usually works well enough, I have a strong suspicion that this is related to some of the quirks that the UI experiences (such as issue #21).

The current scheme also does not cover the case of multiple users editing the same project. For example: let's say users A and B are both logged into the same project. User A adds a stack slightly before user B adds their stack.

User A will only see the stack that they created, and not User B's stack, due to the race condition.
User B, however, will see both stacks since a successful POST leads to soft refresh that will retrieve both created stacks.

Ideally, we should investigate asynchronous technologies (i.e. WebSockets) to handle this behavior.

[bodom0015]

gRPC was brought up as a potential technology that could handle this sort of communication. Unfortunately http://www.grpc.io/faq/ states the following:

Can I use it in the browser?

"Not yet. This is an area that's being actively explored and we welcome feedback and contributions. There is node.js support for server side JavaScript."

[bodom0015]

Things like https://github.com/sercand/grpc-angular have been popping up lately... it's only a matter of time before we can find something suitable.