Add tutorials

[baggepinnen]

This PR adds tutorials corresponding roughly to the topics discussed in #1

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Depended on

• Collection has multiple elements, expected exactly 1 element #14
• add docs #13

[baggepinnen]

I can't quite figure out why a test I added to one of the documentation examples is failing on CI:

┌ Error: failed to run `@example` block in src/tutorials/error_recovery.md:54-58
│ ```@example ERROR
│ treading_lightly() # Warm start
│ allocated_memory = @allocated treading_lightly() # A call that triggers the exception path
│ @test allocated_memory < 1e4
│ ```
│   exception = There was an error during testing

When I run the code locally, I get

julia> allocated_memory
288

[topolarity]

I can't quite figure out why a test I added to one of the documentation examples is failing on CI:

Also fails for me locally if I run julia ./docs/make.jl

Not sure what the root problem is, so for now I've commented out the @test. Documenter has its own Eval loop that it uses to evaluate code, which might be contributing to this.

[topolarity]

Superb work @baggepinnen

I'm very happy to be merging this 👍