also support .dox files

Documentation/Doxygen/Doxyfile.in

-PROJECT_NAME           = CORSIKA8
+PROJECT_NAME           = CORSIKA
+PROJECT_NUMBER         = 8.0.0
 
 OUTPUT_DIRECTORY       = @CMAKE_CURRENT_BINARY_DIR@/
 INPUT                  = @CMAKE_CURRENT_SOURCE_DIR@/../.. 
+EXCLUDE_PATTERN        = "*/ThirdParty/*/*"
 
 GENERATE_HTML          = YES
 GENERATE_LATEX         = NO
 
-FILE_PATTERNS          = *.cc *.h
+FILE_PATTERNS          = *.cc *.cpp *.cxx *.h *.dox
 RECURSIVE              = YES
 
 SOURCE_BROWSER         = YES

ThirdParty/ThirdParty.dox

+/**
+@page ThirdParty
+@tableofcontents
+
+In the directory ThirdParty we provide simple dependencies. This
+minimizes the need to install additional software for the user. Note
+the individual copyrights and licences here!
+
+
+@section PhysUnits
+
+The PhysUnits library is an external dependency included here just for
+convenience: 
+
+Original source code from: https://github.com/martinmoene/PhysUnits-CT-Cpp11#references
+
+Licence: BSL-1.0 (https://github.com/martinmoene/PhysUnits-CT-Cpp11/blob/master/LICENSE_1_0.txt)
+
+References: https://github.com/martinmoene/PhysUnits-CT-Cpp11#references
+
+
+@section catch2
+ 
+The catch2 unit testing library is from: https://github.com/catchorg/Catch2
+Licence: BSL-1.0 (https://github.com/martinmoene/PhysUnits-CT-Cpp11/blob/master/LICENSE_1_0.txt)
+References: https://github.com/catchorg/Catch2
+
+*/

corsika.dox

+/**
+@mainpage CORSIKA air shower simulations 
+
+Source code documentation and reference guide for the CORSIKA8
+software framework for air shower simulations.
+
+
+*/