Adds examples to common build

Adds gitignore file

Renamed to QtCommercialChart

Added size hint for the widget

Adds pimpl to qchart class

Fixed compilation of test/example apps

The test app now preserves series type selection

Refactor xyplotdata * rename xyplotdata to xyplotdomain * add proper initialization list to constructor * change xylinechartitem update interface

Cleanup not used classes * chartview * qchartgraphicswidget

Fix missing file from one of the prvious commits * adds qchartseries.h