Merge pull request #141 from paveljanik/patch-4

Add missing hyphen

Author: ben

book/05-distributed-git/sections/contributing.asc

@@ -41,8 +41,8 @@ The Git project provides a document that lays out a number of good tips for crea
 First, you don't want to submit any whitespace errors.
 Git provides an easy way to check for this – before you commit, run `git diff --check`, which identifies possible whitespace errors and lists them for you.
 
-.Output of `git diff -check`.
-image::images/git-diff-check.png[Output of `git diff -check`.]
+.Output of `git diff --check`.
+image::images/git-diff-check.png[Output of `git diff --check`.]
 
 If you run that command before committing, you can tell if you're about to commit whitespace issues that may annoy other developers.