removes unnecessary sqlite3 gem

Gemfile

@@ -3,8 +3,8 @@ source 'https://rubygems.org'
 
 # Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
 gem 'rails', '4.2.3'
-# Use sqlite3 as the database for Active Record
-gem 'sqlite3'
+# Use PostgreSQL
+gem 'pg'
 # Use SCSS for stylesheets
 gem 'sass-rails', '~> 5.0'
 # Use Uglifier as compressor for JavaScript assets
@@ -35,7 +35,6 @@ gem 'acts-as-taggable-on'
 gem "responders"
 gem 'foundation-rails'
 gem 'acts_as_votable'
-gem 'pg'
 
 group :development, :test do
   # Call 'byebug' anywhere in the code to stop execution and get a debugger console

Gemfile.lock

@@ -173,7 +173,6 @@ GEM
       actionpack (>= 3.0)
       activesupport (>= 3.0)
       sprockets (>= 2.8, < 4.0)
-    sqlite3 (1.3.10)
     thor (0.19.1)
     thread_safe (0.3.5)
     tilt (1.4.1)
@@ -216,7 +215,6 @@ DEPENDENCIES
   sass-rails (~> 5.0)
   sdoc (~> 0.4.0)
   spring
-  sqlite3
   turbolinks
   uglifier (>= 1.3.0)
   web-console (~> 2.0)