Switch database to PostgreSQL

Some tweaks were needed to the schema.rb file because of duplicate index
names and a issue with a `limit: 1` being added to boolean columns - for
further information see rails/rails#19066[1].

[1]: rails/rails#19066

.travis.yml

@@ -7,5 +7,5 @@ before_install:
 before_script:
   - bundle install
   - cp config/database.yml.travis config/database.yml
-  - mysql -e 'create database epets_test;'
+  - psql -c 'create database epets_test;' -U postgres
 script: bundle exec rake

Gemfile

@@ -9,7 +9,7 @@ gem 'responders'
 gem 'rails_autolink'
 
 gem 'rake'
-gem 'mysql2'
+gem 'pg'
 gem 'authlogic'
 gem 'will_paginate'
 gem 'sunspot_rails'

Gemfile.lock

@@ -133,10 +133,10 @@ GEM
     minitest (5.6.1)
     multi_json (1.11.0)
     multi_test (0.1.2)
-    mysql2 (0.3.18)
     newrelic_rpm (3.11.2.286)
     nokogiri (1.6.6.2)
       mini_portile (~> 0.6.0)
+    pg (0.18.1)
     pickle (0.5.1)
       cucumber (>= 0.8)
       rake
@@ -285,9 +285,9 @@ DEPENDENCIES
   json
   launchy
   memcache-client
-  mysql2
   newrelic_rpm
   nokogiri
+  pg
   pickle
   poltergeist
   pry

config/database.yml.example

@@ -1,5 +1,5 @@
 defaults : &defaults
-  adapter: mysql2
+  adapter: postgresql
   encoding: utf8
   username: epets
   password:

config/database.yml.travis

@@ -1,5 +1,5 @@
 test: &TEST
-  adapter: mysql2
+  adapter: postgresql
   database: epets_test
   encoding: utf8
   username: root

db/schema.rb

@@ -27,7 +27,7 @@
     t.string   "first_name",           limit: 255
     t.string   "last_name",            limit: 255
     t.string   "role",                 limit: 10,                 null: false
-    t.boolean  "force_password_reset", limit: 1,   default: true
+    t.boolean  "force_password_reset",             default: true
     t.datetime "password_changed_at"
     t.datetime "created_at"
     t.datetime "updated_at"
@@ -91,10 +91,10 @@
     t.text     "rejection_text",          limit: 65535
     t.datetime "closed_at"
     t.integer  "signature_count",         limit: 4,     default: 0
-    t.boolean  "response_required",       limit: 1,     default: false
+    t.boolean  "response_required",                     default: false
     t.text     "internal_response",       limit: 65535
     t.string   "rejection_code",          limit: 50
-    t.boolean  "notified_by_email",       limit: 1,     default: false
+    t.boolean  "notified_by_email",                     default: false
     t.string   "duration",                limit: 2,     default: "12"
     t.datetime "email_requested_at"
     t.datetime "get_an_mp_email_sent_at"
@@ -121,7 +121,7 @@
     t.integer  "petition_id",      limit: 4
     t.datetime "created_at"
     t.datetime "updated_at"
-    t.boolean  "notify_by_email",  limit: 1,   default: false
+    t.boolean  "notify_by_email",              default: false
     t.datetime "last_emailed_at"
     t.string   "encrypted_email",  limit: 255
   end
@@ -144,16 +144,16 @@
     t.integer  "petition_id",      limit: 4
     t.datetime "created_at"
     t.datetime "updated_at"
-    t.boolean  "notify_by_email",  limit: 1,   default: false
+    t.boolean  "notify_by_email",              default: false
     t.datetime "last_emailed_at"
   end
 
-  add_index "signatures_pre_encryption", ["email", "petition_id", "name"], name: "index_signatures_on_email_and_petition_id_and_name", unique: true, using: :btree
-  add_index "signatures_pre_encryption", ["petition_id", "email"], name: "index_signatures_on_petition_id_and_email", using: :btree
-  add_index "signatures_pre_encryption", ["petition_id", "state", "name"], name: "index_signatures_on_petition_id_and_state_and_name", using: :btree
-  add_index "signatures_pre_encryption", ["petition_id", "state"], name: "index_signatures_on_petition_id_and_state", using: :btree
-  add_index "signatures_pre_encryption", ["state"], name: "index_signatures_on_state", using: :btree
-  add_index "signatures_pre_encryption", ["updated_at"], name: "index_signatures_on_updated_at", using: :btree
+  add_index "signatures_pre_encryption", ["email", "petition_id", "name"], name: "index_signatures_pre_enc_on_email_and_petition_id_and_name", unique: true, using: :btree
+  add_index "signatures_pre_encryption", ["petition_id", "email"], name: "index_signatures_pre_enc_on_petition_id_and_email", using: :btree
+  add_index "signatures_pre_encryption", ["petition_id", "state", "name"], name: "index_signatures_pre_enc_on_petition_id_and_state_and_name", using: :btree
+  add_index "signatures_pre_encryption", ["petition_id", "state"], name: "index_signatures_pre_enc_on_petition_id_and_state", using: :btree
+  add_index "signatures_pre_encryption", ["state"], name: "index_signatures_pre_enc_on_state", using: :btree
+  add_index "signatures_pre_encryption", ["updated_at"], name: "index_signatures_pre_enc_on_updated_at", using: :btree
 
   create_table "sponsors", force: :cascade do |t|
     t.string   "encrypted_email",  limit: 255