0.9.0

• Added strokeWidth, getStrokeColor, getDotColor in the FlDotData, also removed dotColor from it (you should use getDotColor instead, it gives you more customizability), now we have more customizability on FlDotData, check line_chart_sample3, and line_chart_sample5, #233, #99, #274.
• Added equatable library to solve some equation issues.
• Implemented negative values feature for the BarChart, #106, #103.
• add Equatable for all models, it leads to have a better performance.
• Fixed a minor touch bug in the BarChart.
• Fixed ScatterChart built-in touch behaviour.
• Fixed drawing grid lines bug, #280.
• Implemented FlDotData.getDotColor in a proper way, it returns a color based on the LineChartBarData color, #274, #282.
• Updated LineChartData.showingTooltipIndicators field type to list of ShowingTooltipIndicators to have a clean naming.