Add a season ticket calculator

[stephenyeargin]

This is a quick-hit utility for a visitor to see what kind of investment he or she would need to make in a ticket pool to receive a share of the tickets. The first phase of this would not actually interact with the user account at all (does not require a login to use).

I've got a work-in-progress branch that contains the layout and some light coffeescript work to automate the first half of the form. The bottom half is not complete/buggy.

Long term vision for this page would be to improve the UI/UX to be a little less cookie-cutter. Eventually, this concept will make its way into the application as an option when setting up a ticket group for the new season.

/cc @slyeargin