Provide a way to translate the "Today" message inside the DatePicker

[svetq]

Describe the bug
Currently there is no way to translate the "Today" message located inside the DatePicker, that is in the header of the Scheduler component. There should be a property in the kendo-scheduler-messages component that allows to change the "Today" message.

[danielkaradachki]

Available as calendarToday in the latest dev version.

[danielkaradachki]

Released in 0.15.0

https://stackblitz.com/edit/angular-52a2uf?file=app/app.component.ts