Update embed_images script and test icons/images in app

[paddy-r]

Currently not working, but required to compile all images into Python script for portability/packaging. From #7: Images used for icons in app not displaying properly: some shown as black or white rectangles in app.

• Investigate cause and fix
• Test "embed_images" script -> check being rendered properly (check in test app)
• Test whether displaying properly in GUI app (using main app)
• Check that encoded images are actually used, rather than basic image files that are converted during embed_images

[paddy-r]

Fixed with #37 Edited since, not all fixed.