git difftool using meld on OSX

1. 下載 meld
https://yousseb.github.io/meld/

2. 加入下列程式碼在 ~/.gitconfig
```
[diff]
    tool = meld

[difftool]
    prompt = false

[difftool "meld"]
    trustExitCode = true
    cmd = open -W -a Meld --args \"$LOCAL\" \"$PWD/$REMOTE\"
 
```

別人介紹的blog
http://www.alexkras.com/how-to-run-meld-on-mac-os-x-yosemite-without-homebrew-macports-or-think/