Re: [PATCH 9/9] gc: add `gc.repackFilterTo` config option

> A previous commit implemented the `gc.repackFilter` config option
> to specify a filter that should be used by `git gc` when
> performing repacks.
>
> Another previous commit has implemented
> `git repack --filter-to=<dir>` to specify the location of the
> packfile containing filtered out objects when using a filter.
>
> Let's implement the `gc.repackFilterTo` config option to specify
> that location in the config when `gc.repackFilter` is used.
>
> Now when `git gc` will perform a repack with a <dir> configured
> through this option and not empty, the repack process will be
> passed a corresponding `--filter-to=<dir>` argument.
>
> Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
> ---