Update to Proto v0.5.0 (open-telemetry#1588)

* chore: updating submodule for opentelemetry-proto

* chore: necessary changes after upgrade to proto ver. 0.5.0, aligning metrics to latest spec changes

* chore: removing examples from lerna bootstrap

* chore: cleaning ups unused interfaces

* chore: fixing unit test

* chore: updating aggregation temporality rules

* chore: updating temporality for value recorder

* chore: removing unneeded lib

* chore: span id and trace id as hex

* chore: adding value recorder to example

Author: obecny

api/src/metrics/Metric.ts

@@ -59,6 +59,11 @@ export interface MetricOptions {
    * User provided logger.
    */
   logger?: Logger;
+
+  /**
+   * Boundaries optional for histogram
+   */
+  boundaries?: number[];
 }
 
 export interface BatchMetricOptions extends MetricOptions {