Add edit_line and Apply button that shows a comic
Show how to use image.path to change the image
Make is show initial comic, then change when a different number is put in edit_line and Apply is clicked
Add "Dinosaur Comics" title; add placeholder Previous and Next buttons
Get comic to change when pressing Previous or Next
Move Comic Number and Apply button to the top; Move "Dinosaur Comics" to the bottom, between Prev and Next
Add example code to Apply button so that the URL can be checked that it's not a 404 before changing the URL
Move Prev/Next bottom to above the comic, so they don't go up and down as the comic is loading
Center top buttons and text above the comic
Center comic
Add initial URL checking code, where "No Image Available" is displayed if no image
Add new @image_url valid-check to Previous/Next buttons
Remove old comment; add new todo item
Add initial version of class code
Add window frame for class version, with placeholder para to show it works
Demonstrate comic image inside of class version
Remove old para placeholders and unnecessary code
Add para, edit_line, and Apply button above comic in class version
Add placeholder method set_image in class version, to switch images
Add initial code for set_image placeholder method for class version