add screen reader text for icons, titles for text input placeholders
add screen-reader button to measure add data criteria to patient
Assist screenreader users in skipping the header
fixes focus/tab order issue on patient builder

when a button that is clicked on becomes disabled or hidden, this makes sure that the focus is moved to an appropriate object so that the user's focus doesn't then start at the top of the page
make tabs on measure page focusable, with a pointer cursor
change title from "email@example.com" to "email"
Merge pull request #132 from projecttacoma/508_compliance

add 508 compliance