Open Stack

Hi, I'd like you to take a look at this patch for potential
DocImpact.
https://review.openstack.org/24418

Log:
commit c0398786741c275a17e2a5a27c883c4d8adc8b54
Author: Matthew Sherborne <msherborne at gmail.com>
Date:   Thu Mar 14 21:58:33 2013 +1000

    Allow a certain amount of spare servers in each cell
    
    In order to accomodate for chassis swaps and/or emergency migrations,
    cells and scheduler should allow a configurable option for minimum spare
    hosts.
    
    This patch adds a host filterer that either allows or blocks all hosts
    depending on the number of spare (empty) servers free.
    
    DocImpact
    Fixes: bug #1154790
    Change-Id: I9f26bc8ed616d3a39558939033d052cd3f3f3a55