Connect to the remote if it hasn't been done yet, negotiate with
the remote git which objects are missing, download and index the
packfile.
The .idx file will be created and both it and the packfile with be
renamed to their final name.
@param remote the remote
@param refspecs the refspecs to use for this negotiation and
download. Use null or an empty array to use the base refspecs
@param opts the options to use for this fetch
@return 0 or an error code
Download and index the packfile
Connect to the remote if it hasn't been done yet, negotiate with the remote git which objects are missing, download and index the packfile.
The .idx file will be created and both it and the packfile with be renamed to their final name.
@param remote the remote @param refspecs the refspecs to use for this negotiation and download. Use null or an empty array to use the base refspecs @param opts the options to use for this fetch @return 0 or an error code