Use a git-ignored database.yml file for test DB configuration

.gitignore

@@ -1,2 +1,3 @@
 coverage/*
+config/database.yml
 *.DS_Store

config/database.yml.example

@@ -0,0 +1,6 @@
+test:
+  adapter: mysql
+  username: root
+  password: password
+  encoding: utf8
+  database: sql_algebra_test

spec/spec_helper.rb

@@ -6,15 +6,9 @@ $LOAD_PATH.unshift "#{dir}/../lib"
 Dir["#{dir}/matchers/*"].each { |m| require "#{dir}/matchers/#{File.basename(m)}" }
 require 'active_relation'
 
-ActiveRecord::Base.configurations = {
+FileUtils.cp("#{dir}/../config/database.yml.example", "#{dir}/../config/database.yml") unless File.exist?("#{dir}/../config/database.yml")
-  'test' => {
+
-    :adapter  => 'mysql',
+ActiveRecord::Base.configurations = YAML::load(IO.read("#{dir}/../config/database.yml"))
-    :username => 'root',
-    :password => 'password',
-    :encoding => 'utf8',
-    :database => 'sql_algebra_test',
-  },
-}
 ActiveRecord::Base.establish_connection 'test'
 
 class Hash