Create device model and setup devise, activeadmin and rspec!

- with attributes: model, imei_number, unique_id and access_token
 - access_token is automatically generated on create

db/migrate/20151016121927_devise_create_admin_users.rb

@@ -0,0 +1,42 @@
+class DeviseCreateAdminUsers < ActiveRecord::Migration
+  def change
+    create_table(:admin_users) do |t|
+      ## Database authenticatable
+      t.string :email,              null: false, default: ""
+      t.string :encrypted_password, null: false, default: ""
+
+      ## Recoverable
+      t.string   :reset_password_token
+      t.datetime :reset_password_sent_at
+
+      ## Rememberable
+      t.datetime :remember_created_at
+
+      ## Trackable
+      t.integer  :sign_in_count, default: 0, null: false
+      t.datetime :current_sign_in_at
+      t.datetime :last_sign_in_at
+      t.inet     :current_sign_in_ip
+      t.inet     :last_sign_in_ip
+
+      ## Confirmable
+      # t.string   :confirmation_token
+      # t.datetime :confirmed_at
+      # t.datetime :confirmation_sent_at
+      # t.string   :unconfirmed_email # Only if using reconfirmable
+
+      ## Lockable
+      # t.integer  :failed_attempts, default: 0, null: false # Only if lock strategy is :failed_attempts
+      # t.string   :unlock_token # Only if unlock strategy is :email or :both
+      # t.datetime :locked_at
+
+
+      t.timestamps null: false
+    end
+
+    add_index :admin_users, :email,                unique: true
+    add_index :admin_users, :reset_password_token, unique: true
+    # add_index :admin_users, :confirmation_token,   unique: true
+    # add_index :admin_users, :unlock_token,         unique: true
+  end
+end

db/migrate/20151016121931_create_active_admin_comments.rb

@@ -0,0 +1,19 @@
+class CreateActiveAdminComments < ActiveRecord::Migration
+  def self.up
+    create_table :active_admin_comments do |t|
+      t.string :namespace
+      t.text   :body
+      t.string :resource_id,   null: false
+      t.string :resource_type, null: false
+      t.references :author, polymorphic: true
+      t.timestamps
+    end
+    add_index :active_admin_comments, [:namespace]
+    add_index :active_admin_comments, [:author_type, :author_id]
+    add_index :active_admin_comments, [:resource_type, :resource_id]
+  end
+
+  def self.down
+    drop_table :active_admin_comments
+  end
+end

db/migrate/20151016122334_create_devices.rb

@@ -0,0 +1,12 @@
+class CreateDevices < ActiveRecord::Migration
+  def change
+    create_table :devices do |t|
+      t.string :model
+      t.string :unique_id
+      t.string :imei_number
+      t.string :access_token
+
+      t.timestamps null: false
+    end
+  end
+end