REFACTOR: Better handle corner cases
REFACTOR: Better handle corner cases

Without this change, if a chunk has data that should start with a line
break, we were removing it which causes a signature does not much
error.

scality/S3,tomateos/S3,scality/S3,tomateos/S3,scality/S3,tomateos/S3,scality/S3,tomateos/S3,tomateos/S3,scality/S3,scality/S3,scality/S3,tomateos/S3,tomateos/S3,tomateos/S3,scality/S3