Optimize key refresh: O(N^2) -> O(NlogN)
Optimize key refresh: O(N^2) -> O(NlogN)

svn path=/trunk/kdepim/; revision=355885

lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi