Ummm... unmemFTP!

A quick implementation of a StorageBackend for unFTP that returns static files from memory — Is intended for testing things that access FTP, and code-quality-wise, you probably don't want to use it outside of your dev-dependencies.

See the tests for simple usage examples.

Currently only supports reads. Implementing writes may require implementing some sharing mechanism between different instances of the storage backend, but shouldn't be too difficult.