Add initial Microsoft Teams support

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

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

@@ -0,0 +1,13 @@
+// Code generated by msgraph-generate.go DO NOT EDIT.
+
+package msgraph
+
+// Directory undocumented
+type Directory struct {
+	// Entity is the base model of Directory
+	Entity
+	// DeletedItems undocumented
+	DeletedItems []DirectoryObject `json:"deletedItems,omitempty"`
+	// FeatureRolloutPolicies undocumented
+	FeatureRolloutPolicies []FeatureRolloutPolicy `json:"featureRolloutPolicies,omitempty"`
+}