upgraded to C++17 compatibility

bootstrap.sh

@@ -129,7 +129,7 @@ GENERATED FILES
     * ${MY_NAME}
     * autogen.sh - just the basics to initialize auto tools and create configure
     * ax_init_standard_project.m4 - auxiliary macro definition file
-    * ax_cxx_compile_stdcxx_11.m4 - auxiliary macro definition file
+    * ax_cxx_compile_stdcxx.m4 - auxiliary macro definition file
     * ax_check_qt.m4 - auxiliary macro definition file
     * makefile_test.inc.am - makefile to be included in tests
     * resolve-debbuilddeps.sh - script to install debian package dependencies
@@ -274,7 +274,7 @@ FILES
       * Enable C++ testing using CppUnit: AX_USE_CPPUNIT
       * Enable other tests: AX_BUILD_TEST
       * Enable C++ examples, i.e. for libraries: AX_BUILD_EXAMPLES
-      * Check for C++11 support: AX_CXX_COMPILE_STDCXX_11 (see ax_cxx_compile_stdcxx_11.m4)
+      * Require C++17 support: AX_CXX_COMPILE_STDCXX([17], [noext], [mandatory]) (see ax_cxx_compile_stdcxx.m4)
       * Require a QT module: AX_REQUIRE_QT (see ax_check_qt.m4)
       * Optionally use a QT module: AX_CHECK_QT  (see ax_check_qt.m4)
       * Require a module: AX_PKG_REQUIRE (see ax_init_standard_project.m4)
@@ -591,7 +591,7 @@ fi
 # Initialize the environment:
 copy ${MY_NAME}
 copy ax_init_standard_project.m4
-copy ax_cxx_compile_stdcxx_11.m4
+copy ax_cxx_compile_stdcxx.m4
 copy ax_check_qt.m4
 copy makefile_test.inc.am
 copy resolve-debbuilddeps.sh
@@ -1505,6 +1505,7 @@ if testtag AX_USE_DOXYGEN; then
     if ! checkfile doc/doxyfile.in || \
         contains doc/doxyfile.in "${rebuildfiles[@]}"; then
         run doxygen -g doc/doxyfile.in
+        sed -i ':a;/\\$/{s///;N;s/ *\n */ /g;ba}' doc/doxyfile.in
         if test $exists -eq 0; then
             if test -n "${VCS}" -a $novcs -eq 0 && ! contains "doc/doxyfile" "${excludevcs[@]}"; then
                 run ${VCS} add doc/doxyfile.in
@@ -1548,6 +1549,7 @@ if testtag AX_USE_DOXYGEN; then
         doxyreplace WARN_IF_UNDOCUMENTED NO
         doxyreplace WARN_LOGFILE doxygen.errors
         doxyreplace INPUT "@top_srcdir@/src"
+        doxyadd INPUT "@top_srcdir@/@README_FILE@"
         if testtag AX_USE_SCRIPTS; then
             doxyadd INPUT "@top_srcdir@/scripts"
         fi
@@ -1562,6 +1564,7 @@ if testtag AX_USE_DOXYGEN; then
             doxyadd EXCLUDE "@top_srcdir@/nodejs/node_modules"
 	    doxyadd EXCLUDE "@top_srcdir@/nodejs/public/javascripts/ext"
         fi
+        doxyreplace USE_MDFILE_AS_MAINPAGE "@top_srcdir@/@README_FILE@"
         doxyreplace FILE_PATTERNS '*.c *.cc *.cxx *.cpp *.c++ *.java *.ii *.ixx *.ipp *.i++ *.inl *.idl *.ddl *.odl *.h *.hh *.hxx *.hpp *.h++ *.cs *.d *.php *.php4 *.php5 *.phtml *.inc *.m *.markdown *.md *.mm *.dox *.py *.f90 *.f *.for *.tcl *.vhd *.vhdl *.ucf *.qsf *.as *.js *.wt *.sql'
         doxyreplace RECURSIVE YES
         doxyreplace EXCLUDE_PATTERNS "moc_* uic_* qrc_* version.[ch]xx"
@@ -1571,9 +1574,7 @@ if testtag AX_USE_DOXYGEN; then
         doxyreplace HTML_DYNAMIC_SECTIONS YES
         doxyreplace DISABLE_INDEX NO
         doxyreplace GENERATE_TREEVIEW YES 
-        if testtag AX_BUILD_EXAMPLES; then
-            doxyreplace EXAMPLE_PATH @top_srcdir@/examples
-        fi
+        doxyreplace EXAMPLE_PATH @top_srcdir@
         doxyreplace EXAMPLE_RECURSIVE YES
         doxyreplace FILTER_PATTERNS '*.wt=doxygen-webtester.sed *.sql=@top_srcdir@/sql-to-dot.sed'
         doxyreplace SOURCE_BROWSER YES
@@ -1874,7 +1875,7 @@ desktop_DATA = @PACKAGE_DESKTOP@
 dist_pkgdata_DATA = @PACKAGE_ICON@
 dist_noinst_DATA = ax_check_qt.m4 bootstrap.sh				\\
                    resolve-rpmbuilddeps.sh autogen.sh			\\
-                    ax_cxx_compile_stdcxx_11.m4 build-in-docker.sh	\\
+                    ax_cxx_compile_stdcxx.m4 build-in-docker.sh	        \\
                     build-resource-file.sh				\\
                     ax_init_standard_project.m4				\\
                     mac-create-app-bundle.sh resolve-debbuilddeps.sh    \\