rfpdf compatibility with Rails 2.1 fix.
Merged r1612 from trunk.
Escapes HTML tags.
Fixes quick jump to a revision.
Fixed: issues always created with default tracker (#1553).
Fixes relative paths to images in wiki_syntax.html (#1218).
Fixed: Comment too long message when updating issue (#1550).
Redirects back after clicking watch/unwatch links without javascript (#1337).
Removes no longer needed helper method (r1605).
Makes issue update link work without javascript (#1337).
