Changes to POST /api/v1.0/labels

the response's body type changed from array to object for status 201

added the optional property color to the response with the 201 status

added the optional property description to the response with the 201 status

added the optional property is_auto to the response with the 201 status

added the optional property threads to the response with the 201 status

added the required property display_name to the response with the 201 status

added the required property id to the response with the 201 status

added the required property mailbox to the response with the 201 status

added the required property name to the response with the 201 status

added the required property slug to the response with the 201 status