Many edits to record reference docs

Add documentation for aSub from wiki.
Fix incorrect document structures.
Remove inclusion of menu.dbd files.
Fix links to common doc's, remove some links to nowhere.
Adjust podToHtml.pl and the rule that calls it.

src/tools/podToHtml.pl

@@ -16,8 +16,7 @@ use warnings;
 use FindBin qw($Bin);
 use lib ("$Bin/../../lib/perl", $Bin);
 
-use Getopt::Std;
-$Getopt::Std::STANDARD_HELP_VERSION = 1;
+use EPICS::Getopts;
 
 use EPICS::PodHtml;
 
@@ -52,9 +51,10 @@ Help, display this document as text.
 
 =item B<-s>
 
-Indicates that the first component of the input file path is not part of the
+Indicates that one leading component of the input file path is not part of the
 final installation path, thus should be removed before calculating the relative
-path to the style-sheet file.
+path to the style-sheet file. This flag may be repeated as many times as needed
+to remove multiple leading components from the path to the style sheet.
 
 =item B<-o> file.html
 
@@ -87,7 +87,7 @@ if (!$opt_o) {
 }
 
 # Calculate path to style.css file
-shift @inpath if $opt_s; # Remove leading ..
+shift @inpath while $opt_s--; # Remove leading ..
 my $root = '../' x scalar @inpath;
 
 open my $out, '>', $opt_o or