Update Build to Go 1.7
Update Build to Go 1.7

This patch updates the REX-Ray build to use Go 1.7.

oppodeldoc/rexray,thecodeteam/rexray,emccode/rexray,thecodeteam/rexray,oppodeldoc/rexray,codedellemc/rexray,codedellemc/rexray,thecodeteam/rexray,cduchesne/rexray,thecodeteam/rexray,thecodeteam/rexray,cduchesne/rexray,emccode/rexray,oppodeldoc/rexray,oppodeldoc/rexray,cduchesne/rexray,akutz/rexray,thecodeteam/rexray,akutz/rexray,akutz/rexray,akutz/rexray,emccode/rexray,akutz/rexray,codedellemc/rexray,codedellemc/rexray,codedellemc/rexray,codedellemc/rexray,cduchesne/rexray,oppodeldoc/rexray,akutz/rexray,emccode/rexray,oppodeldoc/rexray,cduchesne/rexray,cduchesne/rexray