Add .PHONY for each makefile instruction
Add .PHONY for each makefile instruction

Makes it much easier to keep this maintained properly. See also:

http://clarkgrubb.com/makefile-style-guide#phony-targets

Replaces #1164

Signed-off-by: Ben Firshman <73675debcd8a436be48ec22211dcf44fe0df0a64@firshman.co.uk>

dimaspivak/docker-py,vpetersson/docker-py,auready/docker-py,docker/docker-py,bfirsh/docker-py,funkyfuture/docker-py,kaiyou/docker-py,kaiyou/docker-py,docker/docker-py,youhong316/docker-py,auready/docker-py,bfirsh/docker-py,vpetersson/docker-py,funkyfuture/docker-py,dimaspivak/docker-py,vdemeester/docker-py,youhong316/docker-py,vdemeester/docker-py