Type union for possible ways to describe location of title in ChartXY.

Use with setTitlePosition:

 // Example, place title inside series area.
ChartXY.setTitlePosition(ChartXYTitlePositionOptions.SeriesCenterTop)

ChartXY.setTitlePosition('left-top')
 // Example, align title with Y axis.
ChartXY
.setTitlePosition(ChartXYTitlePositionOptions.LeftTop)
.setTitleMargin({ left: 60 })
.getDefaultAxisY().setThickness(60)