Add savings goals

[kbaley]

Implement a very basic mechanism for savings goals.

You define one or more goals you want to save for along with their priority and amount. Then the total of all the bank accounts is automatically assigned based on the priority.

• create goals page
• create a new goal
• edit an existing goal (slider for the amount?)
• delete an existing goal
• show goals in list by priority along with what percentage has been met
• show total of all bank accounts
• show a visualization (thermometer style with each goal stacked by priority?)

Sample goals:

• Buffer fund
• New car
• Vacation
• Education