[Enhancement] Docker support Debugging (byebug & pry) and receive emails to MailHog via smtp (#371)

* updated development docker setup

* turned on yarn integrity check

* create test docker compose and update development dockerfile

* create docker Readme.md file

* fix README.md file

* create docker-copmose and dockerfile for production/staging environment setup

* added mailhog to catch email

* remove yarn integrity check in development mode!

* Update Readme.md file to support mailhog inbox

* update link to docker development guide from mail README

* remove .env.development and use .env.example for docker as .env.development was mixing with circleci config

* make the dockerfile configurable like before

* update docker-compose as per suggesion in PR

* create docker setup docs

* Revert accidental deletion

* fix: typo for branding consistency

* fix typo

* update the code as per recommendation in PR

* remove package-lock and add gitignore

* fix vulnerability AND update env for tests to pass

* Fix yarn integrity check across different docker services

* update code based on rubocop and PR suggestions

* remove redundant test docker-compose and dockerfile

* update rails entrypoint, update docs and Gemfile

* [Rubocop] order Gemfile alphabetically

* Reordering Gemfile

docker-compose.production.yaml

@@ -0,0 +1,54 @@
+version: '3'
+
+services:
+  base: &base
+    build:
+      context: .
+      dockerfile: ./docker/Dockerfile
+      args:
+        BUNDLE_WITHOUT: ''
+        RAILS_ENV: 'production'
+        RAILS_SERVE_STATIC_FILES: 'true'
+    image: chatwoot:latest
+
+  rails:
+    <<: *base
+    image: chatwoot:latest
+    depends_on:
+      - postgres
+      - redis
+    ports:
+      - 3000:3000
+    env_file: .env.example ## Change this file for customised env variables
+    environment:
+      - NODE_ENV=production
+      - RAILS_ENV=production
+    entrypoint: docker/entrypoints/rails.sh
+    command: ["bundle", "exec", "rails", "s", "-p", "3000", "-b", "0.0.0.0"]
+
+  postgres:
+    image: postgres:9.6
+    restart: always
+    ports:
+      - '5432:5432'
+    volumes:
+      - postgres:/data/postgres
+    environment:
+      - POSTGRES_DB=chatwoot
+      - POSTGRES_USER=postgres
+      - POSTGRES_PASSWORD=
+
+  redis:
+    image: redis:alpine
+    restart: always
+    volumes:
+      - redis:/data/redis
+    ports:
+      - '6379:6379'
+
+volumes:
+  postgres:
+  redis:
+  bundle:
+  packs:
+  node_modules_rails: