Added scaffolding

This is from https://github.com/TheLartians/ModernCppStarter/

documentation/Doxyfile

@@ -0,0 +1,35 @@
+# SPDX-FileCopyrightText: 2023 github.com/TheLartians
+#
+# SPDX-License-Identifier: CC0-1.0
+
+# Configuration for Doxygen for use with CMake
+# Only options that deviate from the default are included
+# To create a new Doxyfile containing all available options, call `doxygen -g`
+
+# Get Project name and version from CMake
+PROJECT_NAME = @DOXYGEN_PROJECT_NAME@
+PROJECT_NUMBER = @DOXYGEN_PROJECT_VERSION@
+
+# Add sources
+INPUT = @DOXYGEN_PROJECT_ROOT@/README.md @DOXYGEN_PROJECT_ROOT@/include @DOXYGEN_PROJECT_ROOT@/documentation/pages
+EXTRACT_ALL = YES
+RECURSIVE = YES
+OUTPUT_DIRECTORY = @DOXYGEN_OUTPUT_DIRECTORY@
+
+# Use the README as a main page
+USE_MDFILE_AS_MAINPAGE = @DOXYGEN_PROJECT_ROOT@/README.md
+
+# set relative include paths
+FULL_PATH_NAMES = YES
+STRIP_FROM_PATH = @DOXYGEN_PROJECT_ROOT@/include @DOXYGEN_PROJECT_ROOT@
+
+# We use m.css to generate the html documentation, so we only need XML output
+GENERATE_XML = YES
+GENERATE_HTML = NO
+GENERATE_LATEX = NO
+XML_PROGRAMLISTING = NO
+CREATE_SUBDIRS = NO
+
+# Include all directories, files and namespaces in the documentation
+# Disable to include only explicitly documented objects
+M_SHOW_UNDOCUMENTED = YES