hibernate mapping for read only user
allow user to be created as read only
disable read-only users to log in
disable read-only users access of the backend api
check method name in order to distinguish read only api calls
authenticate user before invoking API methods

doing user authentication during API invocation was a potentional security issue
as the getLoggedInUser call was not mandatory for cases where no user is needed
doing user retrieval before api call invoking will prevent this as every call
will now have to pass through getLoggedInUser method which validates sessionKey
start using User as parameter instead of sessionKey in ActivationKeyHandler

+ fix ActivationKeyHandlerTest
start using User as parameter instead of sessionKey in ErrataHandler

+ fix ErrataHandlerTest
start using User as parameter instead of sessionKey in SatelliteHandler

+ fix SatelliteHandlerTest
start using User as parameter instead of sessionKey in CryptoKeysHandler

+ fix CryptoKeysHandlerTest
start using User as parameter instead of sessionKey in KeysHandler

+ fix KeysHandlerTest
start using User as parameter instead of sessionKey in SoftwareHandler

+ fix SoftwareHandlerTest
start using User as parameter instead of sessionKey in SystemDetailsHandler

+ fix SystemDetailsHandlerTest
start using User as parameter instead of sessionKey in ProfileHandler

+ fix ProfileHandlerTest
start using User as parameter instead of sessionKey in FilePreservationListHandler

+ fix FilePreservationListHandlerTest
start using User as parameter instead of sessionKey in KickstartTreeHandler

+ fix KickstartTreeHandlerTest
start using User as parameter instead of sessionKey in SnippetHandler

+ fix SnippetHandlerTest
start using User as parameter instead of sessionKey in KickstartHandler

+ fix KickstartHandlerTest
start using User as parameter instead of sessionKey in PreferencesLocaleHandler

+ fix PreferencesLocaleTest
start using User as parameter instead of sessionKey in DistChannelHandler

+ fix DistChannelTest