Added Homebrew formula and instructions

Author: ludocode

README.md

@@ -63,6 +63,12 @@ msgpack-tools is available in the [AUR](https://aur.archlinux.org/packages/msgpa
 
     yaourt -S msgpack-tools
 
+### OS X
+
+A Homebrew formula for msgpack-tools is [included](https://github.com/ludocode/msgpack-tools/blob/master/tools/msgpack-tools.rb) in the repository. This requires [Homebrew](http://brew.sh/).
+
+    brew install https://raw.githubusercontent.com/ludocode/msgpack-tools/master/tools/msgpack-tools.rb
+
 ### Other
 
 For other platforms, msgpack-tools currently must be built from source. The latest version of the msgpack-tools source archive should be downloaded from the releases page. This includes the library dependencies and has pre-generated man pages:

tools/msgpack-tools.rb

@@ -0,0 +1,16 @@
+# Homebrew formula for msgpack-tools
+# Maintainer: Nicholas Fraser <[email protected]>
+class MsgpackTools < Formula
+  desc "Command-line tools for converting between MessagePack and JSON"
+  homepage "https://github.com/ludocode/msgpack-tools"
+  url "https://github.com/ludocode/msgpack-tools/releases/download/v0.4/msgpack-tools-0.4.tar.gz"
+  version "0.4"
+  sha256 "6ca77477ed47ccf4ac882ace3ee5f33a7bc7b929d12c5f10fa0c8fb5874fbc10"
+
+  depends_on "cmake" => :build
+
+  def install
+    system "./configure", "--prefix=#{prefix}"
+    system "make", "install"
+  end
+end