Smoke attribute implies gate attribute
Smoke attribute implies gate attribute

The smoke attribute now implies that the gate attribute
be applied as well. This should simplify the attribute
marking and reduce the probability of tests accidentally
not being included in the gate.

Partially implements blueprint set-gate-attribute

Change-Id: Ic273b216d8702c670bfbff60616bf4d07185c3c8

sorenh/tempest-lib,cneill/tempest-lib,afaheem88/tempest-lib,JioCloud/tempest-lib,varunarya10/tempest-lib,mtreinish/tempest-lib