Inject clear information about instance-, proxy- and client id into the proxy instance

[bheisen]

Is your feature request related to a problem? Please describe.

When working in browser context it can be quite helpful to distinguish the different RPC requests triggered by user interaction. Most of the time we will have a proxy object in hand and hence it would be extremely useful to be able to access the information directly from there.

Describe the solution you'd like

Injecting the public variables:

vrpcClientId
vrpcInstanceId
vrpcProxyId

into the proxy instance.

Describe alternatives you've considered

Alternatively or better additionally the VRPC remote client could provide a public getter function for the vrpcClientId.

Additional context

The addition of the before mentioned properties should reflect non-breaking changes and could be simply added.

[create-issue-branch]

Branch feature/49-inject-clear-information-about-instance--proxy--and-client-id-into-the-proxy-instance created!