upgrade rails & point to gh or bmndr.com/urlminder

Gemfile

@@ -1,26 +1,24 @@
-ruby '2.6.3'
 source 'https://rubygems.org'
 
 # Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
-gem 'rails', '4.0.0'
+gem 'rails' 
+gem 'devise' 
 
-gem 'devise', '3.0.0.rc'
-
-gem 'mongoid', github: 'mongoid/mongoid'
+gem 'mongoid'
 gem 'omniauth'
 gem 'omniauth-beeminder'
 gem 'beeminder'
 
 gem 'httparty'
 
 # Use SCSS for stylesheets
-gem 'sass-rails', '~> 4.0.0'
+gem 'sass-rails'
 
 # Use Uglifier as compressor for JavaScript assets
-gem 'uglifier', '>= 1.3.0'
+gem 'uglifier'
 
 # Use CoffeeScript for .js.coffee assets and views
-gem 'coffee-rails', '~> 4.0.0'
+gem 'coffee-rails' 
 
 # See https://github.com/sstephenson/execjs#readme for more supported runtimes
 # gem 'therubyracer', platforms: :ruby
@@ -32,17 +30,16 @@ gem 'jquery-rails'
 gem 'turbolinks'
 
 # Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
-gem 'jbuilder', '~> 1.2'
-
-group :doc do
-  # bundle exec rake doc:rails generates the API under doc/api.
-  gem 'sdoc', require: false
-end
+gem 'jbuilder' 
 
 group :production do
   gem 'rails_12factor'
 end
 
+group :development do
+  gem 'thin'
+end
+
 # Use ActiveModel has_secure_password
 # gem 'bcrypt-ruby', '~> 3.0.0'