README lacks usage instructions for Rack::Excpetions

[gretel]

bit confusing in regards how other middleware is being configured. might help beginners:

use Rack::Exceptions, Exceptions::Backends::Logger.new

personally i'd like it this way:

use Rack::Exceptions, backend: :raiser

[ejholmes]

Thanks for the suggestion! I'll definitely update the readme.

Regarding the backend: :raiser, I'm hesitant to add things like this because it adds complexity, and makes things less explicit. It's prettier, but is really just an unnecessary layer of abstraction.

[gretel]

partly agree. but what is more important for me than a few lines of abstraction is conformity.. so i'd be happy to initialize ::Exceptions in a syntactically same way as all the others. regards