cleaning up exception mess

apps/encryption/lib/crypto/crypt.php

apps/encryption/lib/exceptions/multikeydecryptexception.php

apps/encryption/lib/exceptions/multikeyencryptexception.php

.../encryption/lib/exceptions/privatekeymissingexception.php

apps/encryption/lib/exceptions/publickeymissingexception.php

apps/encryption/lib/keymanager.php

apps/encryption/lib/session.php

lib/private/connector/sabre/file.php

...ivate/encryption/exceptions/decryptionfailedexception.php

...te/encryption/exceptions/emptyencryptiondataexception.php

...ivate/encryption/exceptions/encryptionfailedexception.php

...ryption/exceptions/encryptionheaderkeyexistsexception.php

...ncryption/exceptions/encryptionheadertolargeexception.php

...te/encryption/exceptions/modulealreadyexistsexception.php

...te/encryption/exceptions/moduledoesnotexistsexception.php

...ivate/encryption/exceptions/publickeymissingexception.php

...te/encryption/exceptions/unexpectedblocksizeexception.php

...n/exceptions/unexpectedendofencryptionheaderexception.php

lib/private/encryption/exceptions/unknowncipherexception.php

lib/private/encryption/keys/storage.php