badwords: re-sync with curl-www, fix issues found

Also:
- replace `manpage` with `man page`, add to `badwords.txt`.
- badwords.pl: import `-w` feature from curl-www, syncing the two
  scripts fully.
- badwords.txt: import missing items from curl-www, syncing the two
  files fully.
- pyspelling.words: drop `cURL` allowed word.

Closes #19468

.github/scripts/badwords.pl

@@ -21,6 +21,24 @@ my @whitelist;
 my %alt;
 my %exactcase;
 
+my %wl;
+if($ARGV[0] eq "-w") {
+    shift @ARGV;
+    my $file = shift @ARGV;
+    open(W, "<$file");
+    while(<W>) {
+        if(/^#/) {
+            # allow #-comments
+            next;
+        }
+        if(/^([^:]*):(\d+):(.*)/) {
+            $wl{"$1:$2:$3"}=1;
+            #print STDERR "whitelisted $1:$2:$3\n";
+        }
+    }
+    close(W);
+}
+
 my @w;
 while(<STDIN>) {
     chomp;
@@ -30,7 +48,7 @@ while(<STDIN>) {
     if($_ =~ /^---(.*)/) {
         push @whitelist, $1;
     }
-    elsif($_ =~ /^([^:=]*)([:=])(.*)/) {
+    elsif($_ =~ /^(.*)([:=])(.*)/) {
         my ($bad, $sep, $better)=($1, $2, $3);
         push @w, $bad;
         $alt{$bad} = $better;
@@ -67,6 +85,14 @@ sub file {
                ($in =~ /^(.*)$w/ && $case) ) {
                 my $p = $1;
                 my $c = length($p)+1;
+
+                my $ch = "$f:$l:$w";
+                if($wl{$ch}) {
+                    # whitelisted
+                    print STDERR "$ch found but whitelisted\n";
+                    next;
+                }
+
                 print STDERR  "$f:$l:$c: error: found bad word \"$w\"\n";
                 printf STDERR " %4d | $in\n", $l;
                 printf STDERR "      | %*s^%s\n", length($p), " ",