added a description property to UserGroup
added UserContextService and implementation
CredentialService no longer needs login name

The logged in user can be obtained from a UserContextService
removed loginName from protection parameters

The logged in user is now obtained from the UserContextService when
needed.
fixed integration test broken by introduction of UserContextService
fixed unit test broken by introduction of UserContextService
now all service beans used by web tier are legitimate EJBs
added the service API for group retrieval and editing
added password generator
added ExportService.generatePassword
set form focus
updated user stories
completed Generate Export Passphrase story
updated user stories
added group editor UI component
revised group editor model to make it easier to use with JSF
group editor now correctly submits new group membership
added support for Create Group interaction
added GroupService implementation and tests
group ID should be a Long