[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

package.json

@@ -7,7 +7,8 @@
     "pretest": "rimraf .jest-cache",
     "test": "jest --no-cache",
     "test:watch": "jest --watch --no-cache",
-    "test:coverage": "jest --no-cache --collectCoverage"
+    "test:coverage": "jest --no-cache --collectCoverage",
+    "webpacker-start": "webpack-dev-server -d --config webpack.dev.config.js --content-base public/ --progress --colors"
   },
   "dependencies": {
     "@babel/polyfill": "^7.6.0",