Feature Request: auto load required plurizers

[honzasterba]

Description

If my understanding is correct, if you want to use different than default pluralizer you need to register when initializing i18n-js. This is different to rails-i18n where pluralizers are loaded based on locale.

Describe the solution

Implement similar mechanism where the locale files included in this lib would optionally refference pluralizer name used for given locale.

If this is in deed a good idea I will prepare a PR.

[fnando]

I'm working on adding support for make-plural package (pr #43), rather than having to re-implement pluralization rules for different languages (like you had to do with #20).

One of the questions I have about automatic activation is related to how to make this work without requiring a bunch of pluralizers that may not necessarily be used, increasing the final bundle size. I'd like to hear your thoughts and see would you approach this problem.

[honzasterba]

What's wrong with loading pluralizers based on activated locales?