A quick fix for mac-osx error: issue #1

[ivanceras]

The documentation from http://doc.crates.io/build-script.html
says cargo:rustc-link-search=native=/path/to/foo

but projects I've used that has c code dependencies and successfully build and run mac osx like rusqlite
uses cargo:rustc-link-search={} without the =native

Removing native in build.rs solves the issue #1

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This change is

[nordstrand]

+1