Add DIL DLL for IXXAT VCI Support

Add a new DLL to support IXXAT Automation GmbH VCI based CAN Interfaces.
DIL_Datatypes.h and DIL_CAN.cpp were updated to support IXXAT hardware now in the application.
Also the build.bat and a new doxyfile to create the source documentation were updated.
To compile it the VCI from the www.ixxat.de must installed and a Windows environment variable 'IXXAT_VCI_SDK' with the path to the VCI header files must created (e.g. IXXAT_VCI_SDK = "c:\Program Files\IXXAT\VCI 3.5\sdk\Microsoft_VisualC").