Quickstart - how to compile

[Hennich]

The quickstart should have a small section on how to compile the example code.
E.g., that you have to explicitly link the library via gcc file.c -lsodium. Compiler commands for other platforms might also be nice.

[jedisct1]

There are many ways to add a library to a project, depending on the compiler, IDE, and build system.

If using the Zig build system, the Git repository is directly going to be added as a dependency.

With cmake, autotools and other Makefile generators, -lsodium is never passed directly either.

With IDEs like Xcode or Visual Studio, this is done by clicking buttons.

Even when being explicit, on many environments, people may also want to use pkg-config instead of -lsodium.

There's nothing special about libsodium compared to other libraries. It's expected to be added to a project the same as any other library.

So documenting this would be a little bit off-topic, and always inacurate/incomplete/outdated compared to the existing documentation of compilers, build systems and IDEs.