Add doxygen documentation

src/docs/build.install-docs

@@ -0,0 +1,21 @@
+build_target docs
+
+# create documentation directories
+echo "Installing documentation into ${DOCSDIR}"
+build_dir_tree "${DOCSDIR}/html" || return 1
+
+# copy across the Doxygen-generated documentation
+for file in html/*
+do
+    install_file ${file} ${DOCSDIR}/html 0644 || return 1
+done
+
+# copy across the generic files
+for file in COPYING README
+do
+    install_file ${file} ${DOCSDIR} 0644 || return 1
+done
+
+print_success "Documentation installed"
+# kate: replace-trailing-space-save true; space-indent true; tab-width 4;
+# vim: expandtab:ts=4:sw=4