Fix the api/client/ps unit tests.
Fix the api/client/ps unit tests.

TestFormat was depending on the time so (comparing again
1970-01-01).. at some point it was bounded to fail >_<. Updating it to
be *not* time-dependent :).

Signed-off-by: Vincent Demeester <87e1f221a672a14a323e57bb65eaea19d3ed3804@sbr.pm>

aditirajagopal/docker,aditirajagopal/docker,aditirajagopal/docker