cleaned up demos

...n/java/org/knowm/xchart/demo/charts/line/LineChart01.java

...n/java/org/knowm/xchart/demo/charts/line/LineChart02.java

...n/java/org/knowm/xchart/demo/charts/line/LineChart03.java

...n/java/org/knowm/xchart/demo/charts/line/LineChart04.java

...n/java/org/knowm/xchart/demo/charts/line/LineChart05.java

...n/java/org/knowm/xchart/demo/charts/line/LineChart06.java

...n/java/org/knowm/xchart/demo/charts/line/LineChart07.java

...ain/java/org/knowm/xchart/demo/charts/pie/PieChart01.java

...ain/java/org/knowm/xchart/demo/charts/pie/PieChart02.java

...ain/java/org/knowm/xchart/demo/charts/pie/PieChart03.java

.../org/knowm/xchart/demo/charts/scatter/ScatterChart01.java

.../org/knowm/xchart/demo/charts/scatter/ScatterChart02.java

.../org/knowm/xchart/demo/charts/scatter/ScatterChart03.java

...java/org/knowm/xchart/demo/charts/stick/StickChart01.java

...java/org/knowm/xchart/demo/charts/theme/ThemeChart01.java

...java/org/knowm/xchart/demo/charts/theme/ThemeChart02.java

...java/org/knowm/xchart/demo/charts/theme/ThemeChart03.java