Add money movers gateway

This is a gateway for http://moneymovers.com/

In active_merchant's current state the tests with this gateway will fail. This gateway has some problems negotiating SSL connections with systems with newer versions of libssl (> 1.0.0). As a result the SSL version needs to be forced.

I submitted a patch (accepted) to active_utils to support this. It is here: https://github.com/Shopify/active_utils/commit/6e5f6047723f1130f0b1a95291a4071393f29c92

If you need this gateway you can use my fork as long as you have

```
gem 'active_utils', :github => 'shopify/active_utils'
```

in your Gemfile.

I am putting this pull request up now so that anyone needing this gateway will have an option and also it could be merged into active_merchant once active_utils pushes a new Gem and active_merchant requires it.