Sort the list of items #42

I have two requests:

1. Can the list of items be sorted? The current implementation does not appear to be sorted in a particular order One implementation would be to sort so the categories are together, eg: those related to deep learning could follow each other or be grouped seperately

2. Can the items be ranked in some way so that beginners can know where to start. The current one has difficulty and uses three squares which are not very clear what they mean.

Adding a screenshot of what the current implementation looks like.