hide submit buttons and use finish button to submit instead

Prevents confusion of having a finish and a submit button.
use javascript to hide the submit buttons as that way non JS browsers
will still be able to see the submit buttons
remove left in instructional text
tidy up checkbox display on diary forms

left as inline-block very long checkboxes would split on to the next
line so the label text was not next to the checkbox. Changing display to
inline and putting the line spacing on the surrounding div fixes this