Production push: homepage member display, older photos, planted from, forex, error messages, firefox links, planted_at bugfix

* Improved homepage member display so the same people don't always show up
* You can now add older photos from Flickr
* There is now a "planted from" field for plantings (eg. seed, cutting, etc)
* Currency conversion links in shop and on order summaries
* Made a bunch of error messages nicer/more grammatical
* Fixed Firefox problem with opening links in new tab
* Fixed bug when editing plantings if "planted at" date was blank