ARM Fixes & Placeholder elimination

These fixes should address the interface errors that occurred when a user selected "Adjustable" Rate Structures.

Also, once a user starts editing the house price, down payment percentage, or down payment amount fields, the placeholder attribute is eliminated. This is done to prevent the placeholder from reappearing when the user deletes or zeros one of those fields.



![selfie-1](http://i.imgur.com/OJxLSzQ.gif)