HaruPage::setLineCap — Set the shape to be used at the ends of lines
( int $cap
Must be one of the following values:
HaruPage::BUTT_END - the line is squared off at the endpoint of the path.
HaruPage::ROUND_END - the end of the line becomes a semicircle with center in the end point of the path.
HaruPage::PROJECTING_SCUARE_END - the line continues to the point that exceeds half of the stroke width the end point.
Returns TRUE on success.