Defer ofHub Execution

[mccow002]

We are using APP_INITIALIZER to load in our config settings. This means that we will not know the base url of our hub until APP_INITIALIZER completes. However, ofHub gets evaluated immediately, causing the following error:
ReferenceError: Attempting to access configuration before it is set.

If the signature of ofHub was changed or overloaded to allow something like this:

ofHub(() => { hubName: 'myHub', url: `${this.configService.baseUrl}/hub` })

I think this would solve any issues caused by having to wait on the APP_INITIALIZER