OpenTelemetry Metrics Support for Live Metrics

[navsukumar]

Do not approve yet, will be making updates to sdk and will have to update the exporter jar files accordingly.

Summary: This PR is linked to the changes proposed in this PR . This PR introduces using a separate Metric Reader to retrieve open telemetry metrics.

SecondEntryPoint: Modified such that a QuickPulseMetricReader instance, whose class is defined in the linked PR, gets instantiated and passed into a QuickPulse instance. This enables the QuickPulse instance to retrieve and export Open Telemetry metrics at any given time.