Chart, Filter, Property, TestSerializer models added and tested working.
BarChart Models
Filter, TestSerializer, Property models.
adds PieRegion, PieLabel, PieData, PieChart models - pieChart specific. Reuses - Property and Metadata existing models. Not tested.
Implemented the ChartAxis superclass, Dimension.java. Stackedchart.java currently in progress
adds sub-packages for the separate chart models
adds Color.java in the common classes
adds Line Chart models- needs review
Stackedbar chart model classes
fixes minor issues with Pie and Line chart
Improve the Stackedbar chart classes
Merge branch 'Feature-models-HAI' of https://github.com/AhmedShafei/HRForecast-WFM into Feature-models-HAI

Conflicts:
	WorkForceManagement/src/de/hrf/workforcemanagement/models/Bar.java
Finish Bar chart
Serialization of the xml (wip)
Fix Stackedbar chart and add toString methods in StackedbarChart and BarChart classes
Merge branch 'Feature-models-HAI' into develop

Conflicts:
	WorkForceManagement/src/de/hrf/workforcemanagement/models/Chart.java