Add ObjNotFound error code.
Add ObjNotFound error code.

Metadata is sending back ObjNotFound as error code.
When services.metadataValidateAuthorization receives this
"error code" it is not an error but merely informative to let
S3 know the object has not already been created.  So the error
should not be returned to the user.

truststamp/S3,truststamp/S3,scality/S3,lucisilv/Silviu_S3-Antidote,tomateos/S3,lucisilv/Silviu_S3-Antidote,scality/S3,tomateos/S3,tomateos/S3,tomateos/S3,lucisilv/Silviu_S3-Antidote,truststamp/S3,truststamp/S3,tomateos/S3,truststamp/S3,scality/S3,scality/S3,lucisilv/Silviu_S3-Antidote,truststamp/S3,truststamp/S3,lucisilv/Silviu_S3-Antidote,tomateos/S3,lucisilv/Silviu_S3-Antidote,tomateos/S3,tomateos/S3,scality/S3,truststamp/S3,scality/S3,lucisilv/Silviu_S3-Antidote,scality/S3,lucisilv/Silviu_S3-Antidote,scality/S3