Use rails convention to underscore collection class names

[rickychilcott]

Bug Fix

Description

This would mean an object such as ActionItem when evaluated in a partial would show up as actionitem by default, instead of the expected action_item. Users of the library could override this with the as: option, such as as: :action_item in this case.

Prior to the change, this code would be need:

<!-- index.html.erb --!>
<%= futurize(collection: ActionItem.all, extends: :div)  { } %>

<!-- _action_item.html.erb --!>
<%= actionitem.description %>

Whereas, we would expect the following to work

<!-- index.html.erb --!>
<%= futurize(collection: ActionItem.all, extends: :div)  { } %>

<!-- _action_item.html.erb --!>
<%= action_item.description %>

Why should this be added

This follows Rails conventions and the principle of least surprise. However, this is a breaking change for users of this library, but is correct in following Rails conventions.

Checklist

• My code follows the style guidelines of this project
• Checks (StandardRB & Prettier-Standard) are passing

[rickychilcott]

Sorry to bombard you @julianrubisch. Real-world use of this library is highlighting a few items for me.

[julianrubisch]

Good catch, keep it coming!

Don't see an issue since we're targeting 1.0 anyway