Date format isn't consistent

[Xodarap]

When saving dates in the provider-patient association code, we call start_date = Time.parse(dates[:start_date]).to_i. This assumes d/m/y format. Displaying dates in that page calls Time.at(perf.start_date).strftime("%m/%d/%y") which is m/d/y. This means that loading the page, making no changes, and saving will result in the dates being changed.

These should either both be m/d/y or d/m/y, depending on who the target audience of popHealth is.

Also client side validation would be good - if I enter 10/31/13 expecting the dates to be in m/d/y format I get the error page because Time.at fails.