[BUG?] Spaces not allowed in directory names in .git/info/attributes

Example session:

    $ git init test.git
    Initialized empty Git repository in /tmp/test.git/.git/
    $ cd test.git
    $ mkdir "dir name"
    $ touch dir\ name/file.txt
    $ echo "dir\\ name/file.txt -text -whitespace" >> .git/info/attributes
    $ git add dir\ name/file.txt
    name/file.txt is not a valid attribute name: .git/info/attributes:1

I'm using

    $ git --version
    git version 2.5.0

Cheers,

-nathan