bug: consecutive attributes are ignored

[hellux]

e.g.

word{.a}{#b}

turns into

Start(Paragraph, {})
Start(Span, {class="a"})
Str("word")
End(Span)
End(Paragraph)

instead of

Start(Paragraph, {})
Start(Span, {class="a", id="b"})
Str("word")
End(Span)
End(Paragraph)

[hellux]

resolved by #30