Provide a view to group news stream according to sites

I guess this is specially helpful for users following a lot of sites' feeds.

The news stream in ZeroHello is like a RSS reader.

Most, if not all RSS readers also provides a view for updated feeds for a specific site,
besides the all new feeds view.

Start by locating the ZeroHello news stream entry point and reviewing how the existing all-news view loads and presents feeds. Define the site-grouped view alongside the current stream, and consider the work done when users can select or access a view showing updates grouped by site.

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