test: boot nsq cluster via docker-compose, update env file

.env files capable of loading configuration that matches the nsq cluster
booted by docker-compose.  Boot docker-compose nsq cluser in CI for live
integration testing.

.env

@@ -0,0 +1,5 @@
+NSQD_TCP_ADDRESS=127.0.0.1:4150
+NSQD_HTTP_ADDRESS=127.0.0.1:4151
+NSQLOOKUPD_TCP_ADDRESS=127.0.0.1:4160
+NSQLOOKUPD_HTTP_ADDRESS=127.0.0.1:4161
+FAKE_QUEUE=true

.travis.yml

@@ -1,11 +1,20 @@
 language: ruby
 cache: bundler
+sudo: false
 rvm:
-  - 2.2.4
   - 2.3.5
   - 2.4.2
+  - 2.5.0
 script:
+  - bundle exec rubocop -D
+  - bundle exec bundle-audit --update
   - bundle exec rake
+services:
+  - docker
+before_install:
+  - docker-compose up -d
+before_script:
+  - gem update --system
 notifications:
   slack:
     rooms:

docker-compose.yml

@@ -0,0 +1,23 @@
+version: '3'
+services:
+  nsqlookupd:
+    image: nsqio/nsq
+    command: /nsqlookupd
+    ports:
+      - "4160:4160"
+      - "4161:4161"
+  nsqd:
+    image: nsqio/nsq
+    command: /nsqd --lookupd-tcp-address=nsqlookupd:4160 --broadcast-address localhost
+    depends_on:
+      - nsqlookupd
+    ports:
+      - "4150:4150"
+      - "4151:4151"
+  nsqadmin:
+    image: nsqio/nsq
+    command: /nsqadmin --lookupd-http-address=nsqlookupd:4161
+    depends_on:
+      - nsqlookupd
+    ports:
+      - "4171:4171"