Add initial Microsoft Teams support

Documentation on https://github.com/42wim/matterbridge/wiki/MS-Teams-setup

vendor/github.com/yaegashi/msgraph.go/beta/CallActivityStatisticsModel.go

@@ -0,0 +1,13 @@
+// Code generated by msgraph-generate.go DO NOT EDIT.
+
+package msgraph
+
+import "time"
+
+// CallActivityStatistics undocumented
+type CallActivityStatistics struct {
+	// ActivityStatistics is the base model of CallActivityStatistics
+	ActivityStatistics
+	// AfterHours undocumented
+	AfterHours *time.Duration `json:"afterHours,omitempty"`
+}