Hide patient builder datepickers on input navigation

### Story ###
- https://www.pivotaltracker.com/story/show/71504922

### Notes ###
- using a <code>blur input</code> event on the patient builder view, hide any open <code>.date-picker</code>'s if the <code>.datepicker</code> class is visible
- this is a prominent issue when attempting to navigate the patient builder form(s) with arrow keys (e.g., with the JAWS screen reader application)