Submitted to SVN. Supports pages, posts and uses server variables to pick up other types of content. Should work in all cases, might need QA for special URLs and content such as WAPreview

We should make the deep link optional for backward compatibility. There will be people who have set a link for their barcodes that now won't show up as it did before (and they might not know why)

Also the barcode link needs to be to the mobile version of this URL, not just the current URL (in the general case - for example when there are different domains.)

I think I've done all the changes required, but it seems overly complex to me. I suggest some semplifications:
- remove the link from the widget settings and just use the default mobile URL as defined in the Switcher
- add a new checkbox (that I have already added for these changes) that lets the user choose between linking to the mobile homepage or deep linking

There is a redundancy at the moment with the URL that I can specify in the widget and it doesn't seem to add anything. There is also a remote chance that users will mess this URL. I do understand that the field was there to allow users for customisation, but what's the point? Either I want to link to the homepage or I want a deep link. The other option is that I deeplink with the 2D barcode to some other page and although I can imagine it as an option, I don't see the use.

If this proposal is "approved by the committee" I'll remove the lines of code and then commit for testing. At this stage in the wpmp_barcode.php there's some over-complexity to deal with all possible combinations.

Another proposed change is that if the user decides to deep link, we change the text that explains what barcode are removing the link to "Our mobile site" or changing the text to something that matches the idea of the deeplink

See r:134170