-Unnecessary using directive
Now draws lines between the two points, rather than a square
Using custom pen to draw a thicker line
Now displays/clears the file name as window title
Now invalidates on Close

This causes the screen to be redrawn to clear the background image.
Ctrl+W now closes the current image
Re-enabling the Maximize/Minimize window buttons
+Save menu item and empty handler, also added hot key and keyboard shortcut
Save menu click handler saves the image
Fixing bug in saveDialog filter
Init'ing filter for saveDlg in designer like openDlg
+AutoSaveTimer, each tick saves to bmp file
If auto-save exists on open, load file. Also changing open to file stream, and fixing Save Dialog bug
Removing code duplication
Removing copy paste autosave file string