Add initial Microsoft Teams support

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

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

@@ -0,0 +1,15 @@
+// Code generated by msgraph-generate.go DO NOT EDIT.
+
+package msgraph
+
+// TimeOffReason undocumented
+type TimeOffReason struct {
+	// ChangeTrackedEntity is the base model of TimeOffReason
+	ChangeTrackedEntity
+	// DisplayName undocumented
+	DisplayName *string `json:"displayName,omitempty"`
+	// IconType undocumented
+	IconType *TimeOffReasonIconType `json:"iconType,omitempty"`
+	// IsActive undocumented
+	IsActive *bool `json:"isActive,omitempty"`
+}