Force line endings when cloning

[yyoncho]

• If we don't force them then depending on the target os the checksum might
  fail.

[Araq]

Shouldn't instead the checksum be made oblivious to the used line endings? But I don't what is better here, just pointing out an alternative.

[yyoncho]

There is already core.autocrlf=false passed as a param so it seems like the decision to go in that direction has already been made.

[Araq]

Ok.