Disallow MySQL and SQLite

Gemfile

@@ -10,7 +10,6 @@ gem "mutations"
 gem "active_model_serializers", "~> 0.8.3"
 gem "ice_cube"
 gem "rack-cors"
-gem "mysql"
 gem "database_cleaner"
 gem "rollbar"
 gem "rack-attack"
@@ -19,9 +18,9 @@ gem "delayed_job_active_record"
 gem "figaro"
 gem "fog-google", git: "https://github.com/fog/fog-google"
 gem "rest-client" # If you see this, delete this.
+gem "pg"
 
 group :development, :test do
-  gem "sqlite3"
   gem "pry"
   gem "factory_girl_rails"
   gem "faker"
@@ -31,14 +30,6 @@ group :development, :test do
   gem "rspec-rails"
 end
 
-group :production do
-  # For Heroku users:
-  gem "pg"
-  # For Dokku users:
-  # TODO: Remove MySQL completly and update Dokku deployment instructions.
-  gem "mysql2"
-end
-
 group :test do
   gem "simplecov"
 end

Gemfile.lock

@@ -126,8 +126,6 @@ GEM
     multi_json (1.12.1)
     mutations (0.8.0)
       activesupport
-    mysql (2.9.1)
-    mysql2 (0.4.5)
     netrc (0.11.0)
     nio4r (1.2.1)
     nokogiri (1.6.8.1)
@@ -227,7 +225,6 @@ GEM
       actionpack (>= 4.0)
       activesupport (>= 4.0)
       sprockets (>= 3.0.0)
-    sqlite3 (1.3.12)
     thin (1.7.0)
       daemons (~> 1.0, >= 1.0.9)
       eventmachine (~> 1.0, >= 1.0.4)
@@ -260,8 +257,6 @@ DEPENDENCIES
   ice_cube
   jwt
   mutations
-  mysql
-  mysql2
   paperclip (~> 5.0.0)
   pg
   pry
@@ -276,7 +271,6 @@ DEPENDENCIES
   rspec-rails
   simplecov
   smarf_doc!
-  sqlite3
   thin
 
 RUBY VERSION