Add initial Microsoft Teams support

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

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

@@ -0,0 +1,15 @@
+// Code generated by msgraph-generate.go DO NOT EDIT.
+
+package msgraph
+
+// ObjectIdentity undocumented
+type ObjectIdentity struct {
+	// Object is the base model of ObjectIdentity
+	Object
+	// SignInType undocumented
+	SignInType *string `json:"signInType,omitempty"`
+	// Issuer undocumented
+	Issuer *string `json:"issuer,omitempty"`
+	// IssuerAssignedID undocumented
+	IssuerAssignedID *string `json:"issuerAssignedId,omitempty"`
+}