chart axis ticks style refactor

pom.xml

.../src/main/java/com/xeiam/xchart/demo/charts/Example1.java

...src/main/java/com/xeiam/xchart/demo/charts/Example10.java

.../src/main/java/com/xeiam/xchart/demo/charts/Example2.java

.../src/main/java/com/xeiam/xchart/demo/charts/Example8.java

.../src/main/java/com/xeiam/xchart/demo/charts/Example9.java

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

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

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

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

...a/com/xeiam/xchart/internal/chartpart/AxisTickLabels.java

...n/java/com/xeiam/xchart/internal/chartpart/AxisTitle.java

...main/java/com/xeiam/xchart/internal/chartpart/Legend.java

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

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

xchart/src/main/java/com/xeiam/xchart/style/theme/Theme.java

...c/main/java/com/xeiam/xchart/style/theme/XChartTheme.java