Do the pango text layout in multiple chunks

Do the pango text layout in multiple chunks

This way we can avoid the need for quoting, since we can just use text
rendering instead of markup for the free-form fields.  And we will want
to make the pango layout width different for the date and location,
since we want to fit the depth/duration to the right of them.

I still haven't set the different width for the date/location, but this
at least is going in the rigth direction.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>