Sets the wrap mode. The wrap mode only has effect if a width is set on the layout
with playout:SetWidth(). To turn off wrapping, set the width to -1.
The following wrap modes are currently supported:
#PANGO_WRAP_WORD-
Wrap lines at word boundaries.
#PANGO_WRAP_CHAR-
Wrap lines at character boundaries.
#PANGO_WRAP_WORD_CHAR-
Wrap lines at word boundaries, but fall back to character boundaries if there is not enough space for a full word.
The default value is #PANGO_WRAP_WORD.