Add CMake example

rust-to-cmake/build.rs

@@ -0,0 +1,11 @@
+extern crate cmake;
+
+fn main() {
+    // Builds the project in the directory located in `libfoo`, installing it
+    // into $OUT_DIR
+    let dst = cmake::build("libdouble");
+
+    println!("cargo:rustc-link-search=native={}", dst.display());
+    println!("cargo:rustc-link-lib=static=double");
+}
+