Add initial Microsoft Teams support

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

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

@@ -0,0 +1,17 @@
+// Code generated by msgraph-generate.go DO NOT EDIT.
+
+package msgraph
+
+// IncomingContext undocumented
+type IncomingContext struct {
+	// Object is the base model of IncomingContext
+	Object
+	// SourceParticipantID undocumented
+	SourceParticipantID *string `json:"sourceParticipantId,omitempty"`
+	// ObservedParticipantID undocumented
+	ObservedParticipantID *string `json:"observedParticipantId,omitempty"`
+	// OnBehalfOf undocumented
+	OnBehalfOf *IdentitySet `json:"onBehalfOf,omitempty"`
+	// Transferor undocumented
+	Transferor *IdentitySet `json:"transferor,omitempty"`
+}