Initial terminal size is now explicitly passed through parameters, providing
better control. Session aborts now produce an error message on the screen.
UI changes. If user has started typing in a new command, double-clicking a filename copies the filename to the cursor position, rather than opening/executing the file.
Improved full screen implementation; added bold and underline styles. Centralized UI event handling. Added checks to limit number of output lines displayed. Added capability to interrupt hung output data streams. Nearing full backwards compatibility with xterm.
Implemented full screen operations in XMLTerm, although still buggy.
Commands like 'less', 'vi', and 'emacs -nw' now work in stand-alone xmlterm,
although scrolling is still messed up. Compiles with Feb21 tree.
