summary: introduce "summaryremotehooks" to avoid redundant incoming/outgoing check This patch introduces "summaryremotehooks" to avoid redundant incoming/outgoing check for "hg summary" in other than "commands.summary". Only if "--remote" is not specified for "hg summary", hooks registered in "summaryremotehooks" are invoked with "None" as "changes" argument at first, and they should return tuple of two booleans meaning "whether incomings are needed" and "whether outgoings are needed". If no hooks return tuple containing "True", "hg summary" does nothing any more, because incoming/outgoing check is not needed. Otherwise, hooks are invoked again: at this time, "changes" argument refers the result of incoming/outgoing check. This patch also prevents RepoError from being raised if "--remote" is not specified for "hg summary", because of backward compatibility for "hg summary --large" without "--remote".

util: enable "hooks" to return list of the values returned from each hooks