Some places, such as GitLab, require a PNG rather than SVG file for
logos.

`nix-shell` is dead, long live ~~`nix-shell`~~ `nix develop`!

Formatting is no longer checked in the normal tests, and old-style tests
no longer run the regression tests so `CairoMakie` isn't needed there
anymore.

They're just regression tests, so their purpose is less to test the code
than it is to just check that we haven't changed things accidentally.

This commit also adds a test for the example, to ensure that the example
stays up-to-date.

I've changed the GitLab URL from `seamsay/meander.jl` to
`seamsay/Meander.jl` to comply with Julia's packaging guidelines.

Add some integration tests to make sure that the output of `show` isn't
changed by accident.

`Path` is the primary use-case for this package. It defines a path
through a space, allowing iteration and easy retrieval of information
needed for plotting.

PkgTemplates version: 0.7.17