v0.4.0

Treats the markdown as the source of truth. This means if a level/step isn't in the config, it will still build.

Allows for the new recommended way of labeling levels/steps:

In markdown:

Level: ## 1. Level one
Step: ### 1.1 A Label (label is optional)
And in commits:

1 Level
1.1 First step commit
1.1S First step solution