Set up to build Rust code with dependencies

cargo-raze is like gazelle, but for Rust code. It generates BUILD files
for external dependencies.

I'm putting this in a separate change from running it and setting up CI
to do that for ease of telling what's generated vs not.

Change-Id: I87a07255dca475514cae7bdbf9b0b62ce46e2512
Signed-off-by: Brian Silverman <bsilver16384@gmail.com>
diff --git a/third_party/cargo/cxx/include.BUILD.bazel b/third_party/cargo/cxx/include.BUILD.bazel
new file mode 100644
index 0000000..f6b9f5a
--- /dev/null
+++ b/third_party/cargo/cxx/include.BUILD.bazel
@@ -0,0 +1,9 @@
+# This file is included in the BUILD for the cxx crate, to export its header
+# file for C++ code to depend on.
+cc_library(
+    name = "cxx_cc",
+    visibility = ["//visibility:public"],
+    hdrs = ["include/cxx.h"],
+    srcs = ["src/cxx.cc"],
+    includes = ["include"],
+)