Since the `u` flag was added to the whitespace regex in TextConverter
(7f03acf), `\s` also matches U+00A0, so ` ` and literal non-breaking
spaces were turned into regular spaces. Leave U+00A0 out of the collapse.
EmphasisConverter used trim(), which does not strip U+00A0, so a
non-breaking space at the edge of <em>/<strong> would now end up inside
the delimiters (`**Total: **`), where it stops them from flanking the
text. Strip it there too; like before, it becomes a regular space outside
the delimiters.
Fixes#258
dualfroz
af172f8665