Currently, I am using Kalendae from https://github.com/ChiperSoft/Kalendae and I have to say it is fantastic. The best part is that I don't have to worry about dependencies.
By default, the calendar pops up when a text box is selected and updates the date, but then I have to click the close [x] button to close the calendar.
I would prefer the calendar to close automatically upon selecting a date. This behavior was confirmed as default on the Demo page as well: http://chipersoft.com/Kalendae/.