issue #25: real-time charts effort.

...n/java/com/xeiam/xchart/demo/charts/line/LineChart04.java

...ain/java/com/xeiam/xchart/standalone/RealtimeAttempt.java

...in/java/com/xeiam/xchart/standalone/RealtimeAttempt2.java

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

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

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

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

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

...xchart/internal/chartpart/AxisTickBarChartCalculator.java

...ava/com/xeiam/xchart/internal/chartpart/ChartPainter.java

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

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

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