update to new versions

results of drush up :

 Drupal                                   7.15               7.17              SECURITY UPDATE available                          
 Diff (diff)                              7.x-2.0            7.x-3.2           Installed version not supported                    
 Entity Reference (entityreference)       7.x-1.0-rc5        7.x-1.0           Update available                                   
 Message (message)                        7.x-1.5            7.x-1.6           Update available                                   
 RedHen Memberships (redhen_membership)   7.x-1.0-beta1      7.x-1.0-beta2     Update available                                   

since there is no patches and all seems to work with these new versions, i'd suggest updating the version references where necessary and creating a newer release so people who download the whole thing don't get old modules.