Convert <iframe> tags embedded in a feed to the corresponding <a> tags pointing to the same target, with text from the title tag if available, or failing that the target URL. The intention is that people who want to embed, eg, youtube videos in their article at least give some means of having that show in the aggregated feed.
Add an option to turn off precompiling (which doesn't really work on Windows)
Ensure that the newly-added href attribute actually makes it through the check for valid attributes
Tweak the iframe handler in respect of allowed attributes