added color parameter
added first dummy version of the color widget
refactoring
added color widget
added first version of the painting method
added color test to the test properties
using now the reset button
the color widget gets updated now when the color has been changed
added QFrame to the widget representation of a QColor
widgets can use now the alpha channel
ColorWidget is now split into two widgets if alpha is used
drawing an alpha-Checkerboard is working now
added status tips
added additional parameter
showing color dialog is working now
Merge branch 'feature-18-add-color-property-representation' into feature-3-refactoring-properties