Fix file delimiter under Windows when using git bash

[abuseofnotation]

Windows uses '' for delimiters, so flow reports 'path/to/file' as 'path\to\file' (which becomes 'pathtofile') when using vim from git bash or other simulated unix env.

Not sure what is the case with gvim.

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[gabelevi]

Can't unix pathnames contain \? Won't this mess with those?

$ touch "foo\\bar.txt"
$ ls foo\\bar.txt 
foo\bar.txt

Of course, it's pretty clowny to have backslashes in directory or filenames, but I worry that this find/replace will break something.

Of course, filenames can also contain ", so the code already is pretty flawed :/