Corrections in mac handling for logical sff

Corrections in mac handling for logical sff

Included changes:
- nextHop: inner dst mac address was being changed instead of
     the one in the eth encapsulation header (fixed). Also, added
     the src mac address, so the packet can be correctly forwarded
     (by switching src and dst mac) after SF processing
- changed src mac address at chain egress so the packet won't
     be dropped because of bad src mac at subsequent pipeline
     stages
- Table 0 (classifier) table is no longer written by Logical
     transport processor in any circumstance (logical SFF is
     always used in cooperation with Genius -> Genius owns
     table 0 always (it is used for service binding)
- Some test improvements

Change-Id: I1f344604801f0855cc35ea27885de91427766f24
Signed-off-by: Diego Granados <diego.jesus.granados.lopez@ericsson.com>