renaming instances of swauth to gswauth

changed code where appropriate to gswauth
instead of swauth

Change-Id: Iadcec4f379fae3f063379b4899797b375290cc7b
Signed-off-by: Thiago da Silva <thiago@redhat.com>
Reviewed-on: http://review.gluster.org/6226
Reviewed-by: Luis Pabon <lpabon@redhat.com>
Tested-by: Luis Pabon <lpabon@redhat.com>