Security fix: Not handling back-slashes properly on Windows lead to all files on e.g. C: being accessible via build-in HTTP server
Security fix: Not handling back-slashes properly on Windows lead to all files on e.g. C: being accessible via build-in HTTP server

(cherry picked from commit babc59cc8613142683149905bef0f595759b1aff)

uroni/urbackup_backend,uroni/urbackup_backend,uroni/urbackup_backend,uroni/urbackup_backend,uroni/urbackup_backend,uroni/urbackup_backend,uroni/urbackup_backend