tidy-up: URLs (cont.) and mdlinkcheck

- add missing ending slashes.
  To avoid duplicates and to use canonical URLs.
- reapply lost updates.
  Follow-up to 2ae983bf4e #19879
- mdlinkcheck: include the `include` directory.
- mdlinkcheck: show unused whitelist items.
- mdlinkcheck: improve debug output.
- mdlinkcheck: delete redundant whitelist items.
- examples/simplessl: lowercase the protocol part.
- BINDINGS: replace one remaining HTTP URL with HTTPS.
  Issue: https://github.com/pycurl/pycurl/issues/892
- BINDINGS: fix a broken link.
- BINDINGS: follow a refresh content redirect.
- KNOWN_BUGS: whitespace.

Closes #19911

scripts/mdlinkcheck

@@ -71,14 +71,12 @@ my %whitelist = (
     'https://curl.se/rfc/rfc2255.txt' => 1,
     'https://curl.se/sponsors.html' => 1,
     'https://curl.se/support.html' => 1,
-    'https://curl.se/windows' => 1,
     'https://curl.se/windows/' => 1,
 
     'https://testclutch.curl.se/' => 1,
 
     'https://github.com/curl/curl-fuzzer' => 1,
     'https://github.com/curl/curl-www' => 1,
-    'https://github.com/curl/curl.git' => 1,
     'https://github.com/curl/curl/wcurl' => 1,
 
     );
@@ -87,7 +85,7 @@ my %url;
 my %flink;
 
 # list all files to scan for links
-my @files=`git ls-files docs src lib scripts`;
+my @files=`git ls-files docs include lib scripts src`;
 
 sub storelink {
     my ($f, $line, $link) = @_;
@@ -103,6 +101,7 @@ sub storelink {
     if($link =~ /^(https|http):/) {
         if($whitelist{$link}) {
             #print "-- whitelisted: $link\n";
+            $whitelist{$link}++;
         }
         # example.com is just example
         elsif($link =~ /^https:\/\/(.*)example.(com|org|net)/) {
@@ -164,7 +163,7 @@ sub findlinks {
         # comma, question mark, colon, closing parenthesis, backslash,
         # closing angle bracket, whitespace, pipe, backtick, semicolon
         elsif(/(https:\/\/[a-z0-9.\/:%_+@-]+[^."'*\#,?:\)> \t|`;\\])/i) {
-            #print "RAW ";
+            #print "RAW '$_'\n";
             storelink($f, $line, $1);
         }
         $line++;
@@ -202,10 +201,16 @@ for my $f (@files) {
     }
 }
 
-#for my $u (sort keys %url) {
-#    print "$u\n";
-#}
-#exit;
+for my $u (sort keys %whitelist) {
+    if($whitelist{$u} == 1) {
+        printf "warning: unused whitelist entry: '$u'\n";
+    }
+}
+
+for my $u (sort keys %url) {
+    print "$u\n";
+}
+exit;
 
 my $error;
 my @errlist;