Add quotes to project path

This fixes an issue when the project path contains spaces

Fixes #116

Author: qgadrian

priv/hook_template

@@ -1,6 +1,6 @@
 #!/bin/sh
 
-[ "$project_path" != "" ] && cd $project_path
+[ "$project_path" != "" ] && cd "$project_path"
 
 $mix_path git_hooks.run $git_hook "$@"
 [ $? -ne 0 ] && exit 1

test/mix/tasks/git_hooks/install_test.exs

@@ -34,7 +34,7 @@ defmodule Mix.Tasks.InstallTest do
 
     ~s(#!/bin/sh
 
-[ "#{app_path}" != "" ] && cd #{app_path}
+[ "#{app_path}" != "" ] && cd "#{app_path}"
 
 mix git_hooks.run #{git_hook} "$@"
 [ $? -ne 0 ] && exit 1