Add comment field to JanosBibliographyStyle

Print the content of "Comment" fields in JanosBibliographyStyle, similar
to how it is done in VancouverBibliographyStyle.

bibtexbrowser.php

@@ -2584,6 +2584,10 @@ function JanosBibliographyStyle($bibentry) {
 
   $result = implode(", ",$entry).'.';
 
+  // some comments (e.g. acceptance rate)?
+  if ($bibentry->hasField('comment')) {
+      $result .=  " (".$bibentry->getField("comment").")";
+
   // add the Coin URL
   $result .=  "\n".$bibentry->toCoins();