Add initial Microsoft Teams support

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

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

@@ -0,0 +1,11 @@
+// Code generated by msgraph-generate.go DO NOT EDIT.
+
+package msgraph
+
+// AddWatermark undocumented
+type AddWatermark struct {
+	// MarkContent is the base model of AddWatermark
+	MarkContent
+	// Orientation undocumented
+	Orientation *PageOrientation `json:"orientation,omitempty"`
+}