Fixing style in ActiveRecord

Removed few spare spaces, little bit fixed definition methods with special access (if two different definition styles are found in one file, changed them to one)

Noticed that we have three different definintion access styles:
1. 
```ruby
class Foo
  def method
  end

  private
   
  def private_method
  end
end 
```
2.
```ruby
class Foo
  def method
  end

private
   
  def private_method
  end
end 
```

3.
```ruby
class Foo
  def method
  end

  private
   
    def private_method
    end
end 
```
Which of this styles is more preferable for using in rails?