Initial design of the Insert Symbol dialog.
Finished bookfile.py full funtionality.
Really got bookfile working this time.
Symbol.py now working

Need to add functionality to BookEntry.py in order to take
advantage of this.
Cleaned up menu option.

Made the 'file' and 'entry' menus options and the buttons more
symmetric. Wrote all the functions. Tested somewhat. Still need
a DisplayToEntry() and the insertChar() function.