gateway: Fix some found typos

gateway: remove empty test file

README: Add document

Makefile: Add e2e target & update clean

gateway/cmd/server: Impl main

zmbdrv/http/cmd/server: Impl main

drvloc/nsqhttp/cmd/server: Impl main

gateway: Define & impl endpoints & ctor

gateway: Create config & func for loading from YAML

zmbdrv/http: Define & impl transport

zmbdrv/drvloc: Impl IsZombie method

zmbdrv/drvloc: Define Service & impl ctor func

modules: Have only one Go module

zmbdrv: Define the service iface and main err codes

drvloc/nsqhttp: Define & impl transport