Merge pull request #30 from tommarshall/git-alias-usage

Add git alias usage to docs

Author: paulirish

readme.md

@@ -24,6 +24,11 @@ git diff --color | diff-so-fancy
 git config --global core.pager "diff-so-fancy | less --tabs=1,5 -R"
 ```
 
+Or, create a git alias  in your `~/.gitconfig` for shorthand fanciness:
+```shell
+diff-so-fancy = "!git diff --color $@ | diff-so-fancy"
+```
+
 ## Install
 
 For convenience, the recommended installation is via NPM: