there used to be a slight bug. Suppose the user types a text in the
input box, and never changes the focus.
Then, she press "Stop". the click and the focus lost happen in nearly
the same moment, which leads to a race in which the name is set only if
the /api/update arrives before the /api/generate.
Sending the message before losing the focus mitigates the issue
Borders in old.html were too light, and on some screens they were not
visible. This changes will make them stronger, and also make input in
new.html behave consistently
Clearer separation of data and its representation of datetime objects in
db: now the db only handles datetime objects and the server will take
care of converting from/to strings with the browser
