Renamed the CPTBarPlot barLengths property to barTips to conform with the field naming convention (location, tip, and base). Fixed issue 334.
Renamed the CPTBarPlot barLengths property to barTips to conform with the field naming convention (location, tip, and base). Fixed issue 334.

aufflick/core-plot,aufflick/core-plot,aufflick/core-plot,aufflick/core-plot,aufflick/core-plot