This change ensures that Git always disables text file line-ending normalisation when cloning changes from a Git remote.

Separate (still to be done) work on the OpamLocal driver, opam admin, and opam lint code will ensure that hashes for text files are always initially computed using the repository normalisation. This differs from the approach of previous PRs which potentially hashed two versions of the file by determining from the git if the file needs transforming prior to the single hash being computed. The only time this transformation comes into play is if a Local (i.e. rsync) remote of a Git clone is added on a platform with core.autocrlf set to true (i.e. if you are working in a Git clone of a remote with core.autocrlf set to true)