properly set up databases in a less cold-drug-addled way

Gemfile

@@ -4,9 +4,13 @@ source 'https://rubygems.org'
 # Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
 gem 'rails', '4.1.4'
 # Use sqlite3 as the database for Active Record
-# gem 'sqlite3'
+group :test, :development do
+  gem 'sqlite3'
+end
 # Swappin'
-gem 'pg'
+group :production do
+  gem 'pg'
+end
 # Use SCSS for stylesheets
 gem 'sass-rails', '~> 4.0.3'
 # Use Uglifier as compressor for JavaScript assets

config/database.yml

@@ -1,10 +1,10 @@
 development:
-  adapter: postgresql
+  adapter: sqlite3
   database: my_database_development
   pool: 5
   timeout: 5000
 test:
-  adapter: postgresql
+  adapter: sqlite3
   database: my_database_test
   pool: 5
   timeout: 5000