Fixes#82.
The old behaviour was to parse the content of a widget or html element
in block mode if the opening tag was followed by a line break. The new
behaviour requires two line breaks.
This makes it possible to include linebreaks more liberally within
wikitext, although care must still be taken to only use double line
breaks when the block mode behaviour is desired.
The code change here is very simple, just a single line change in
html.js. Most of the other changes are to convert various single line
breaks into double line breaks.
Now we get decent visual indication of sync errors, for instance. Still
work to do to coalesce alerts so that the screen doesn’t fill up with
them after an interval. And probably we should add a button to clear
all alerts.
