Replace "Mac" with "OS X"

docs/development/build-instructions-osx.md

@@ -0,0 +1,66 @@
+# Build Instructions (OS X)
+
+Follow the guidelines below for building Electron on OS X.
+
+## Prerequisites
+
+* OS X >= 10.8
+* [Xcode](https://developer.apple.com/technologies/tools/) >= 5.1
+* [node.js](http://nodejs.org) (external)
+
+If you are using the Python downloaded by Homebrew, you also need to install
+following python modules:
+
+* pyobjc
+
+## Getting the Code
+
+```bash
+$ git clone https://github.com/atom/electron.git
+```
+
+## Bootstrapping
+
+The bootstrap script will download all necessary build dependencies and create
+the build project files. Notice that we're using `ninja` to build Electron so
+there is no Xcode project generated.
+
+```bash
+$ cd electron
+$ ./script/bootstrap.py -v
+```
+
+## Building
+
+Build both `Release` and `Debug` targets:
+
+```bash
+$ ./script/build.py
+```
+
+You can also only build the `Debug` target:
+
+```bash
+$ ./script/build.py -c D
+```
+
+After building is done, you can find `Electron.app` under `out/D`.
+
+## 32bit Support
+
+Electron can only be built for a 64bit target on OS X and there is no plan to
+support 32bit OS X in future.
+
+## Tests
+
+Test your changes conform to the project coding style using:
+
+```bash
+$ ./script/cpplint.py
+```
+
+Test functionality using:
+
+```bash
+$ ./script/test.py
+```