Typecasting in control properties

[maddin]

The controls should cast the given values to parameters into the needed type, using the TPropertyValue-methods. For example what problems may occur otherwise, see http://www.pradosoft.com/forum/index.php/topic,9780.0.html For example, the TTextBox::setText-method does not cast to string. Every control should be checked and all properties should get a type cast.

[xue]

We introduce typecasting for properties because controls may be configured in XML and template, where the property values are supplied as strings. Therefore, we do not use ensureString in properties.