rails/rails — pull request #14141 by printercu (2014-02-21 15:20:35+00:00)
Title: Pass instance to I18n when translating error

It'll allow to do like this:
```ruby
# inside model that has .title
validates_numericality_of :quantity, greater_then: 0,
title: ->(h) { h[:instance].title }
```
with translations
```yaml
errors:
models:
my_model:
greater_then: of %{title} must be greater than %{count}
```