Sort order for packages seems off

[tswicegood]

It took me a minute to realize that the Packages list was all packages and that only some of them were installed. We need to rethink this interface.

Couple of possible solutions:

• Move Packages tab to be separate in the UI. Seems like it's more akin to configuration, so maybe it belongs as part of the global "conda" environment (little "e", not a conda ~/anaconda/envs/ environment).
• Sort the table of installed, then alpha
• Create two tables: first is installed packages, second is packages that are immediately available, but not installed

One open question: should you be able to install packages that are in various conda channels, but have not been downloaded into your local packages? If so, how does that fit into the list of packages?

Given the last question, I'm partial to creating a separate area in the UI for packages so we can differentiate between local and remote packages and allow searches to hit the configured servers as well. That said, I think the two table approach might be a solid first step. We might even be able to collapse the Packages and Installed tabs into one.