Connect to the remote if it hasn't been done yet, negotiate with
the remote git which objects are missing, create a packfile with the missing
objects and send it.
@param remote the remote
@param refspecs the refspecs to use for this negotiation and
upload. Use null or an empty array to use the base refspecs
@param opts the options to use for this push
@return 0 or an error code
Create a packfile and send it to the server
Connect to the remote if it hasn't been done yet, negotiate with the remote git which objects are missing, create a packfile with the missing objects and send it.
@param remote the remote @param refspecs the refspecs to use for this negotiation and upload. Use null or an empty array to use the base refspecs @param opts the options to use for this push @return 0 or an error code