Create init method on provider interface

vendor/github.com/Microsoft/ApplicationInsights-Go/appinsights/clock.go

@@ -0,0 +1,11 @@
+package appinsights
+
+// We need to mock out the clock for tests; we'll use this to do it.
+
+import "code.cloudfoundry.org/clock"
+
+var currentClock clock.Clock
+
+func init() {
+	currentClock = clock.NewClock()
+}