EVA Screen Save and Restore

I added in the terminal sequences to save the screen and to restore it when EVA is exited.

Now you can open the editor without losing the entire screen which I'm sure will be handy. Though I might miss quickly opening a file so I can type something out as now I can't get access to TCL while the file is in view.

   ALT.SCREEN = ESCAPE.CODE : '[?1049h'
   REG.SCREEN = ESCAPE.CODE : '[?1049l'
*
   PRINT ALT.SCREEN :
*

Above the escape sequences to switch to the alternative screen and the escape sequence to switch to the regular screen. EVA will run in the alternative screen so that when we switch back to the main screen, everything will still be accessible.

In the exit section, I have another PRINT statement that will print out the regular screen escape code.