Emit stream events in stream_connection.ts

[CJxD]

When using the managedwriter, I found that the connection often needs to reconnect, but my calling code was unable to determine when this happens.

In this commit I have forwarded the various events from the underlying connection, except 'close' is only called when the stream_connection has been instructed to close, and a new event 'reconnect' is emitted when the stream has been closed and reopened.

Fixes #529 🦕

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[CJxD]

I'm having some difficulty with the Google CLA - I have signed it on behalf of the organisation and added the members to our group [email protected] but it doesn't seem to be picking it up.

It might be worth closing this PR and making the changes yourself. I will continue with my workaround for now.

[alvarowolfx]

thanks for the PR @CJxD, I'll take over from here and try to add those improvements.