updating region server load for AssignmentManager

[Ted Yu]

Hi,
I plan to utilize region server load for better balancing.
Currently the following method only calls
serverManager.regionServerReport():
  public HMsg [] regionServerReport(HServerInfo serverInfo, HMsg msgs[],
    HRegionInfo[] mostLoadedRegions)
This means AssignmentManager doesn't have valid server load information.

How about adding the following method to AssignmentManager ?
public void regionServerReport(HServerInfo serverInfo, HRegionInfo[]
mostLoadedRegions)

Please comment.