I got a little sick of trying to keep the export data and <head> links
synched in actions, so I made a common method, getFeeds(), which gets
the feeds for both. It returns an array of Feed objects, which know
about what their mime type is, title, location, all that jazz.
I changed the FeedList class so it handles the new Feed objects
instead of the old array of data.
I changed all the actions that show feeds (I think...) so that they
now use getFeeds() for all their feed needs.
My attempts here are to mimic the `pagination()` method shared by
actions. I'm tentatively adding the `$count` property to actions so that
we can query the number of notices ''being displayed'' per page prior to
calling the actual `pagination()` method itself, since document
relationship `<link>` elements need to be output inside of `showHead()`,
before `showContent()`, which is where `pagination()` is, gets called.
These extra `<link>` elements only appear on pages where pagination
makes sense. They trigger functionality in some user agents, such as
Opera's Navigation Bar for more easily navigating forward and backwards
across a paged set of notices, messages, or group lists, etc.