Move tutorials to new repo and remove manual

[LoganAMorrison]

I think it would be better to isolate the Hazma code and tutorials into separate repositories. It seems like it would be nice to have a standalone HazmaTutorials repository which contains all Jupyter notebooks (similar to DifferentialEquations.jl and its corresponding DiffEqTutorials.jl repository.)

Also, it doesn't seem like we need the manual. I think the paper + docs should be good enough. @adam-coogan, what do you think?

[adam-coogan]

Yeah, that would probably be best. I also agree about not needing a manual -- the paper has a ton of examples.

[LoganAMorrison]

Okay, sounds good. I'll work on this when I get a chance.