Cleanup platform configurations (#399)

* Cleaned up platform configurations and added 'unix' and 'wasm32-unknown-unknown' targets

* Regenerate documentation
diff --git a/rust/platform/BUILD b/rust/platform/BUILD
index 8e7621e..de7aedf 100644
--- a/rust/platform/BUILD
+++ b/rust/platform/BUILD
@@ -1,7 +1,7 @@
-package(default_visibility = ["//visibility:public"])
-
 load(":platform.bzl", "declare_config_settings")
 
+package(default_visibility = ["//visibility:public"])
+
 declare_config_settings()
 
 package_group(