WIP [ci skip]
Added DulHydra::RoleManager class for providing a list of available roles (a.k.a. groups)
Incidentally fixed bug in DulHydra::Grouper::Client and adjusted config value accordingly.
bug fix
Renamed class from DulHydra::RoleManager to DulHydra::RoleService.
Introduces the GroupService class and implements the subclass DulHydra::Services::RemoteGroupService
Along the way ...
DulHydra::Grouper::Client moved to DulHydra::Services::GrouperService
DulHydra::Grouper::User deleted (and removed from the User model)
DulHydra::Models::User overrides Hydra::User#groups to use the RemoteGroupService.
Devise initializer updated to use RemoteGroupService to set user.groups.
Config settings named grouper_groups_* renamed to remote_groups_*.
Fixed bug in User that caused Travis build to fail b/c it lacks a Grouper config file.
Upgraded jettywrapper dev/test dependency to 1.5 b/c 1.4 `jetty:stop' was broken,
Take 2 on squashing bug.
Moved GrouperService config init to Devise initializer
Merge pull request #349 from duke-libraries/role-manager

Group service