Use $GOFLAGS when building map_server Docker image
Use $GOFLAGS when building map_server Docker image

Allows different versions of the image to be built, e.g. one with race
detection.

daviddrysdale/trillian,RJPercival/trillian,gdbelvin/trillian,daviddrysdale/trillian,Martin2112/trillian,AlCutter/trillian,google/trillian,gdbelvin/trillian,RJPercival/trillian,gdbelvin/trillian,AlCutter/trillian,google/trillian,Martin2112/trillian,daviddrysdale/trillian,Martin2112/trillian