Provide an up-to-date, complete set of examples

[jayconrod]

A non-exhaustive list:

• A "hello world" binary.
• Small Go project with a few libraries and tests.
• Go project with cgo files and libraries.
• Go project with vendoring.
• Go project with .pb.go files (Gazelle proto generation disabled).
• Go project with .proto files (Gazelle proto generation enabled).
• Project using a cross-compiling C/C++ toolchain.
• Using custom static analysis tools (when they're merged).

Examples should be Gazelle-friendly, though we may want to include at least one with multiple Go packages in a directory to show that other layouts are possible.

[eriksw]

I'd like to suggest my use case that, as a Bazel newbie, seems dizzyingly complicated if not impossible:

• Go project with a vendored library that uses cgo and needs to link against distro-provided system libraries which are readily available as debs but make zero sense to vendor in themselves. For example: github.com/coreos/go-systemd/sdjournal -> libsystemd-dev, libsystemd0, ...

Having a clear example for how to make Bazel build something like that from an arbitrary host would be incredibly helpful.

[prestonvanloon]

+1 for cross compile with cgo example. I have been struggling for a while to derive examples of linux -> darwin cross compile w/ cgo.