Added sample image file

Wil be used by the Show Picture Feature
Created ShowPictureFeature

When executed, this will show a sample picture
Eexecute Show Picture Feature form Menubar
Implement KeyListener

This will listen for keyboard actions.

Signed-off-by: Ino Gamalinda <ino.gamalinda@teamcodeflux.com>
Switched JWindow to JFrame

Because JWindow doesn't seem to respond on KeyListeners, it might be a bug or a feature.
Close the frame when Escape button is released.

Signed-off-by: Ino Gamalinda <ino.gamalinda@teamcodeflux.com>
Created Screen Dimension Helper

Will be used for getting the screen size and positions.
Utilize the screen dimension helper

For code reuse
Use KeyEvent enums instead of hard coded Key values
Center window location
Added method for relication window position to center
Use center window helper method
Move write to screen feature to JFrame package

Because write to screen feature now uses JFrame because JWindow is buggy
Set variable scope to private explicitly
Disable resizing