Knocking UIs into shape

Env is now called Session, which seems like a much better name.

View, previously TextView, is now the abstract class UI.

And the direct portal now has two UI subclasses.

What this all does is to begin to put the control flows into their new form. The UI is now the manager of the display.

What's next? Well, I need to clean up a bunch of variable names. I also want to start working on the new UI class and eliminate the displays.txt file. Commands will now request displays by passing the display's class object. Once all this is a bit more refined, we can focus on defining display events, so that once again we will not tied to a text display.

And no, I don't anticipate any more reorganizations on this scale. Though I do also want to move the header and default display logic (at least some of it) from the UI class into various Rolon classes. These displays should vary both by the UI mode/class selected by the user/portal and by the type of Rolon being displayed, so its a bit tricky to get right.

Bill