README: don't suggest there is an in-memory backend in this codebase
This is not something we have which can lead to confusion. Use a name that
should make it clearer that it's something to provide.
@@ -577,7 +577,7 @@ You can store bare repositories in alternative backends instead of storing on di
`redbadger/rugged-redis` for an example of how a rugged backend works).
```ruby
-a_backend = Rugged::InMemory::Backend.new(opt1: 'setting', opt2: 'setting')
+a_backend = MyProject::CustomObjectDB(opt1: 'setting', opt2: 'setting')
repo = Rugged::Repository.init_at('repo_name', :bare, backend: a_backend)
