Configure attributes using .gitattributes file
    
    As stated in gitattributes(5):
    	Attributes which should be version-controlled and distributed to
    	other repositories (i.e., attributes of interest to all users)
    	should go into .gitattributes files.
    
    Therefore, move the currently-used attributes to a .gitattributes file.
    This is to support future changes to attributes.
    
    The attributes in $GIT_DIR/info/attributes have precedence over
    .gitattributes. Therefore, users who have run scripts/install-git-hooks
    from a version predating this patch may have attributes in
    $GIT_DIR/info/attributes that override the ones in .gitattributes.
    Unfortunately, we are stuck with this blemish from the past and must
    forever clean up the mess.
    
    - .gitattributes:
    - .gitignore:
    - scripts/install-git-hooks: