Managing the review queue

[dsimcha]

 From observing the review processes for std.parallelism and 
std.net.isemail, I think our review process needs some tweaking.  There 
are two key issues:

1.  The pace of reviews is glacial unless there's a vote date near. 
Only 4 people have reviewed std.net.isemail, and that's counting any 
participation in the discussion as "review".  This module doesn't have a 
vote date yet.  IIRC only two people reviewed std.parallelism during its 
first two weeks of review.  Furthermore, it took some time after I 
requested review for the "official" review period to start.  As a 
solution all requests for review should come with a tentative vote date 
to prevent the module from being held in limbo indefinitely and move the 
review queue along.

2.  Reviews that prompt major changes right before the vote date are 
stressful.  A looming deadline is not conducive to careful discussion 
and consideration of suggestions, especially those that are non-trivial 
to understand and/or implement.

I propose that all review periods last one week for small modules or two 
weeks for large modules, subject to extension if the review process is 
still yielding good discussion near the vote date or "stashing" if the 
author needs time to discuss specific issues that were raised and/or 
design and implement changes.  When a module is stashed, it is no longer 
officially in review and the next item in the review queue, if any, can 
begin the process.  As soon as this item is done, review of the stashed 
item is resumed.  Right now, std.parallelism is stashed until 
std.net.isemail is finished.

To prevent the community from being overwhelmed, multiple reviews may 
not take place concurrently but a review may take place concurrently 
with a vote.  Contention for the review queue is an issue in theory, but 
that's a problem we'd like to have and can work out on an ad-hoc basis 
should it arise.

More specifically, the pace of reviews for std.net.isemail has been 
glacial.  If everyone who intends to review it has done so, we should 
move on to a vote.  If anyone intends to review this module but hasn't 
yet, please do so or at least state your intention to do so.