Allows us to get rid of build.rs, which was only used to
compile resources. static_resource.rs is now created by
meson, and the meson path is used for include_bytes!.
Closes https://gitlab.gnome.org/World/podcasts/issues/55
Previously we were using the env! macro to determine
build-time variables like version, app ID, and locale dir.
Instead of relying on env vars, we can create a configuration
file with meson and import it.
Christopher Davis