Add implementation of Server-Sent Events (SSE)

[evidolob]

Fixes: Issue #N

Relates to: Issue #N, PR #N, ...

Solution/Idea

This PR provides implementation of server sent events. This implementation is used to replace existing WebSocket implementation. Currently only status event channel is used for fetching crc status -w data.

Also PR provide logs event channel on which daemon publish all logs collected by logrus logger, it will be used in future work for moving all crc command execution to daemon, as will allow to keep current cli behaviour/output.

PR uses r3labs/sse/v2 as SSE library

Test

You could use curl to view events:

curl -GET -i --unix-socket <path to crc socket>/crc-http.sock "http://localhost/events?stream=logs" to view logs events.
curl -GET -i --unix-socket <path to crc socket>/crc-http.sock "http://localhost/events?stream=status" to view data which used for crc status -w.

crc status -w should work exactly as before.

[gbraad]

feels almost like a drop-in replacement.

[gbraad]

Fixes: Issue #N

Can you reference the issue this is related to ?

[gbraad]

curl -GET -i --unix-socket <path to crc socket>/crc-http.sock "http://localhost/events?stream=logs" to view logs events.

This also works on Windows?

[gbraad]

crc status -w should work exactly as before.

We need to verify if the following scenario worked the same before:

Only CPU and memory are updated:

PS> .\crc.exe stop -f
PS> .\crc.exe status -w
CRC VM:          Stopped
MicroShift:      Stopped (v4.13.0)
Disk Usage:      0B of 0B (Inside the CRC VM)
Cache Usage:     20.72GB
Cache Directory: C:\Users\gbraad\.crc\cache
... in the mean time in another shell start `.\crc.exe start`
... the status like VM and preset does not change; remain 'Stopped'
... wait a little bit: "INFO Starting Microshift service... [takes around 1min]" ... kill watch process 
PS> .\crc.exe status -w
CRC VM:          Running
MicroShift:      Running (v4.13.0)
Disk Usage:      5.462GB of 16.1GB (Inside the CRC VM)
Cache Usage:     20.72GB
Cache Directory: C:\Users\gbraad\.crc\cache
... the status correctly shows the VM is running.

See #3744

[openshift-ci]

@evidolob: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
ci/prow/e2e-crc	93e9f7f	link	true	/test e2e-crc

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[gbraad]

how to implement this for the extension?
and followup with #3744 to include state

[openshift-ci]

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