fixed min and max axis values

...ain/java/com/xeiam/xchart/demo/charts/bar/BarChart04.java

...n/java/com/xeiam/xchart/demo/charts/line/LineChart01.java

.../com/xeiam/xchart/demo/charts/scatter/ScatterChart02.java

xchart/src/main/java/com/xeiam/xchart/Chart.java

...c/main/java/com/xeiam/xchart/internal/chartpart/Axis.java

...in/java/com/xeiam/xchart/internal/chartpart/AxisTick.java

.../xeiam/xchart/internal/chartpart/PlotContentBarChart.java

...xeiam/xchart/internal/chartpart/PlotContentLineChart.java

...rnal/chartpart/axistickcalculator/AxisTickCalculator.java

...rt/src/main/java/com/xeiam/xchart/style/StyleManager.java

xchart/src/test/java/com/xeiam/xchart/chart/Example2.java

xchart/src/test/java/com/xeiam/xchart/chart/NoBug.java