Fix problem with parsing main UI boot tiddlers

We were parsing the boot tiddlers, making them into a widget and then
refreshing the widget tree. The problem is that subsequent chances to
the boot tiddlers themselves wouldn’t be picked up as part of the
refresh.

Now we indirectly parse those UI boot tiddlers through a transclusion,
which does get refreshed in the desired way.
Add chinese translation of banner for binary tiddlers in edit mode
Update release note
Fix incorrect charset for the previous  commit
Fix problem with list fields containing `[[]]`

Fixes #603 - thanks @xcazin!

It no longer crashes but unfortunately if you round trip a tiddler out
of edit mode and back you’ll lose any empty double square brackets.
Fix problem with parsing lists contain non-breaking spaces

Some of the time we need to treat non-breaking spaces as though they
are not spaces (regexps treat them as spaces by default).
Fix typos in docs for image parser
Implement explicit external links
Merge pull request #602 from BramChen/master

Add chinese translation of banner for binary tiddlers in edit mode