Inject the storage adapter into the mail scraping adapter
Make Ppl::Adapter::EmailScraper::Mail avoid overwriting existing contacts
Pass a storage_adapter into Ppl::Adapter::EmailScraper::Mail
Fix some broken tests
Fix ppl scrape to work with Ppl::Entity::EmailAddress instead of just strings
Version 2.2.0

Thanks again to @pigmonkey for issue #32, reporting some unhelpful destructive
behaviour in ppl scrape. In this version, some additional checking has been
added to that command to prevent it from overwriting existing contacts.

In the event that the scraped contact ID happens to match that of an existing
contact, ppl scrape will now notice this collision and append numbers to the new
ID until it no longer matches any existing contact’s IDs.