Modifying title block linking

The AutoCAD title block link can be configured as usual. The document type templates update the title line properties based on attribute changes. The Discipline property is updated when the title lines are updated. Be aware that the Description property is updated by concatenating the title line fields in the function RecalcDrawingDescription. A good place to update the title is the PropertyChange_* event handlers for the most common properties. By default, the configuration overwrites the behavior of the following properties: ProjectName1, VersionNumber, and RevisionDerivedFrom using the function DocCADLink_BeforeWriteProperty.