Feed statuses

[goodboy]

Since #164, we've had multi-feed streaming for charts but it would sure be handy if you would get a overall status of a particular provider connection possibly in the new status bar introduced in #189 as well as possibly through some kind of aggregate feed widget eventually. Further it'd be handy to have a way to restart a provider if it goes down, seems slow, or has an error through some kind of manual control.

Couple ideas:

• offer a feed status widget in the status bar (kind like our mode label) that you can mouse interact with and possibly restart / respawn feeds through a context menu?
• offer a way to possibly re-route where a feed is draw from for down the road when we have aggregate data daemons running shared for a group of traders

More ideas welcome from the lurks!