Save preferences

[rsouth]

2 things:
Save preferences to file, read on startup.
No file should exist to begin with, it's just saved to store state of the app .
If fail to save, ignore (maybe app is being run from inside a zip.

Properties:

• window location
• currently open file

http://commons.apache.org/proper/commons-configuration/

2 - put the filename of the currently open file in the tab title.
Put a star on the title when the state is dirty.
Add a close button to the tab to close the current document.
No file means 'untitled'.