Issue title: As a Fedora Linux user, I want to easily see updates for packages I have installed on my machine so I can give them karma
 Issue body: I realise this is probably something that is considered out of scope for Bodhi, but if we do want to get more users providing feedback, it'll be nice if:

- bodhi can figure out what packages are installed on my Fedora Linux installation (probably needs some sort of browser extension like the gnome-shell one)
- let me choose what packages I care about and remember them---most users don't know what the underlying libraries are etc., so theyre' not going to be confident enough to provide karma for them
- have a page where I see only these packages I care about, and let me easily provide karma for them.

I know there is fedora-easy-karma, and fedora-update-feedback, but:

- they're TUIs, and I cannot see normal end-users using them to provide karma
- at the moment I'm not aware of a way to limit them to packages I care about (will file RFEs)

If this can be somehow integrated into Bodhi itself, we can start trying to get Fedora Linux users to also provide karma, instead of the really small set of QA volunteers, who cannot cover every package there is.
 Comments: 
 Comment 0: Note too there **was** this:

https://pagure.io/fedora-qa/fedora-gooey-karma
 Comment 1: Yeh, but somehow having to install an extra tool already makes it slightly more work, especially for users that get spooked easily by technical contribution roles. If it can all be part of the one main web interface that's our go-to place for updates info, all these additional specialist tools will no longer be required.
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