Update hooks should have a description in there docblock

[andybroomfield]

Noting update 10001

 ---------------------- ----------- --------------- -------------------- 
  Module                 Update ID   Type            Description         
 ---------------------- ----------- --------------- -------------------- 
  localgov_subsites_pa   10001       hook_update_n   10001 - Implements  
  ragraphs                                           hook_update_N().    
 ---------------------- ----------- --------------- -------------------- 

This docblock should actually be a description of what the update does instead of the implements hook notation.