Use fnameescape to quote filenames for :badd.

[zacharyvoase]

When you move a file in NERDTree's FS menu, and a buffer is already open with it, you're prompted to delete the old buffer and replace it with a new buffer pointing to the file's new location. This wasn't working correctly for me: because the new filename is passed to badd quoted with single quotes, Vim just created a new buffer pointing to a file called '/Users/zack/.../filename' with the quotes. See the odd results of this when trying to rename a file in the nerdtree source tree:

This patch uses the fnameescape() function to do the filename escaping, rather than just surrounding with single quotes. I've tested it and it fixes the error seen in the above screenshot.

[PhilRunninger]

👍 I've noticed this before. Thanks for the fix, @zacharyvoase.