Don't use confusing (GIT_DIR) variable name

$GIT_DIR is used for the actual .git dir,
not the root of the repository.  So pick a better variablename

Author: Dieterbe

git-ignore-wizard

@@ -25,20 +25,20 @@ dirname=` dirname  $file`
 basename=`basename $file`
 case $type in
 	.gitignore-root)
-		GIT_DIR=`git root $file` || exit 2
+		root=`git root $file` || exit 2
 		dirname=$(readlink -f $dirname)
-		relative_dir=$(echo $dirname | sed "s#^$GIT_DIR##") # ie: /src
-		echo "$relative_dir/$basename" >> $GIT_DIR/.gitignore
+		relative_dir=$(echo $dirname | sed "s#^$root##") # ie: /src
+		echo "$relative_dir/$basename" >> $root/.gitignore
 		;;
 	.gitignore-dirname)
 		git root $file >/dev/null || exit 2
 		echo "$basename" >> $dirname/.gitignore
 		;;
 	exclude)
-		GIT_DIR=`git root $file` || exit 2
+		root=`git root $file` || exit 2
 		dirname=$(readlink -f $dirname)
-		relative_dir=$(echo $dirname | sed "s#^$GIT_DIR##")
-		echo "$relative_dir/$basename" >> $GIT_DIR/info/exclude
+		relative_dir=$(echo $dirname | sed "s#^$root##")
+		echo "$relative_dir/$basename" >> $root/info/exclude
 		;;
 	.gitconfig)
 		#TODO. git config --get-all ?, then another dmenu? how many such config keys are allowed?