[CSS] Font size hierarchy refactor
[PLUGINS][MediaFeed] Renamed BeforeFeed event
Type scale hierarchy redone. Bigger line height added, making it easier
to click on links and separate contents.
Feed title added. AddFeedActions replaces BeforeFeed event.
MediaFeed links will now show an icon to the right of the feed title,
smaller footprint and more consistent with the overall design.
For reference (raised by rozzin in IRC):
* http://foldoc.org/module
* http://foldoc.org/library
* http://foldoc.org/plugin
As noted by XRevan86, modules are not necessarily non-essential.
As we will keep the modules directory in GS root [therefore, near to
plugins/], it is evidenced the difference between both.
This is a simple yet fundamental structural change. It doesn't change
functionality but makes clearer the way we understand GNU social's
internals.
