Upgrade to rails 6 💎 (#11)

- upgraded to rails 6
- fixes various issues

.ruby-version

@@ -1 +1 @@
-2.4.0
+2.6.0

Gemfile

@@ -1,35 +1,38 @@
+# frozen_string_literal: true
+
 source 'https://rubygems.org'
-ruby '2.4.0'
 
-gem 'rails', '~> 5.0.0', '>= 5.0.0.1'
+ruby '2.6.0'
+
+# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
+gem 'rails', '~> 6', github: 'rails/rails'
 gem 'sass-rails', '~> 5.0'
 gem 'puma', '~> 3.0'
 gem 'uglifier', '>= 1.3.0'
-gem 'coffee-rails', '~> 4.2'
+gem 'coffee-rails'
 gem 'therubyracer', platforms: :ruby
 gem 'jbuilder', '~> 2.5'
-gem 'redis', '~> 3.0'
-gem 'devise'
+gem 'redis'
+gem 'devise', git: 'https://github.com/plataformatec/devise'
 gem 'pg'
 gem 'facebook-messenger', '~> 0.11.1'
 gem 'sidekiq'
 gem 'koala'
 gem 'omniauth-facebook'
 gem 'rest-client'
 gem 'telegram-bot-ruby'
-gem 'devise_token_auth'
-gem 'pusher'
+gem 'devise_token_auth', git: 'https://github.com/lynndylanhurley/devise_token_auth'
 gem 'responders'
 gem 'kaminari'
 gem 'rack-cors', :require => 'rack/cors'
-gem 'acts-as-taggable-on', '~> 4.0'
+gem 'acts-as-taggable-on', git: 'https://github.com/mbleigh/acts-as-taggable-on'
 gem 'sinatra', github: 'sinatra'
 gem 'wisper', '2.0.0'
 gem 'nightfury', '~> 1.0', '>= 1.0.1'
 gem 'redis-namespace'
 gem 'redis-rack-cache'
-gem 'redis-rails'
 gem 'figaro'
+gem 'pusher'
 gem 'pundit'
 gem 'carrierwave-aws'
 gem 'mini_magick'
@@ -40,6 +43,7 @@ gem 'chargebee', '~>2'
 gem 'poltergeist'
 gem 'phantomjs', :require => 'phantomjs/poltergeist'
 gem 'time_diff'
+gem 'bootsnap'
 
 
 # Windows does not include zoneinfo files, so bundle the tzinfo-data gem
@@ -53,10 +57,9 @@ group :development, :test do
   gem 'byebug', platform: :mri
   gem 'letter_opener'
   gem 'web-console'
-  gem 'listen', '~> 3.0.5'
+  gem 'listen'
   gem 'spring'
-  gem 'spring-watcher-listen', '~> 2.0.0'
+  gem 'spring-watcher-listen'
   gem 'seed_dump'
-  gem 'mailcatcher'
   gem 'rubocop', '~> 0.74.0', require: false
 end