Suppress the to_s on the Client object

The `to_s` on heroics is gargantuan - here's a sample:

```
on"=>"state of account feature", "example"=>"public", "readOnly"=>true, "type"=>["string"]}, "updated_at"=>{"description"=>"when account feature was updated", "example"=>"2012-01-01T12:00:00Z", "format"=>"date-time", "readOnly"=>true, "type"=>["string"]}}, "links"=>[{"description"=>"Info for an existing account feature.", "href"=>"/account/features/{(%23%2Fdefinitions%2Faccount-feature%2Fdefinitions%2Fidentity)}", "method"=>"GET", "rel"=>"self", "title"=>"Info"}, {"description"=>"List existing account features.", "href"=>"/account/features", "method"=>"GET", "rel"=>"instances", "title"=>"List"}, {"description"=>"Update an existing account feature.", "href"=>"/account/features/{(%23%2Fdefinitions%2Faccount-feature%2Fdefinitions%2Fidentity)}", "method"=>"PATCH", "rel"=>"update", "schema"=>{"properties"=>{"enabled"=>{"$ref"=>"#/definitions/account-feature/definitions/enabled"}}, "required"=>["enabled"]}, "title"=>"Update"}], "properties"=>{"created_at"=>{"$ref"=>"#/definitions/account-feature/definitions/created_at"}, "description"=>{"$ref"=>"#/definitions/account-feature/definitions/description"}, "doc_url"=>{"$ref"=>"#/definitions/account-feature/definitions/doc_url"}, "enabled"=>{"$ref"=>"#/definitions/account-feature/definitions/enabled"}, "id"=>{"$ref"=>"#/definitions/account-feature/definitions/id"}, "name"=>{"$ref"=>"#/definitions/account-feature/definitions/name"}, "state"=>{"$ref"=>"#/definitions/account-feature/definitions/state"}, "updated_at"=>{"$ref"=>"#/definitions/account-feature/definitions/updated_at"}}}, "account"=>{"description"=>"An account represents an individual signed up to use the Heroku platform.", "id"=>"schema/account", "$schema"=>"http://json-schema.org/draft-04/hyper-schema", "stability"=>"production", "title"=>"Heroku Platform API - Account", "type"=>["object"], "definitions"=>{"allow_tracking"=>{"default"=>true, "description"=>"whether to allow third party web activity tracking", "example"=>true, "type"=>["boolean"]}, "beta"=>{"default"=>false, "description"=>"whether allowed to utilize beta Heroku features", "example"=>false, "type"=>["boolean"]}, "created_at"=>{"description"=>"when account was created", "example"=>"2012-01-01T12:00:00Z", "format"=>"date-time", "readOnly"=>true, "type"=>["string"]}, "email"=>{"description"=>"unique email address of account", "example"=>"username@example.com", "format"=>"email", "type"=>["string"]}, "id"=>{"description"=>"unique identifier of an account", "example"=>"01234567-89ab-cdef-0123-456789abcdef", "format"=>"uuid", "readOnly"=>true, "type"=>["string"]}, "identity"=>{"anyOf"=>[{"$ref"=>"#/definitions/account/definitions/email"}, {"$ref"=>"#/definitions/account/definitions/id"}]}, "last_login"=>{"description"=>"when account last authorized with Heroku", "example"=>"2012-01-01T12:00:00Z", "format"=>"date-time", "readOnly"=>true, "type"=>["string"]}, "name"=>{"description"=>"full name of the account owner", "example"=>"Tina Edmonds", "readOnly"=>false, "type"=>["string"]}, "new_password"=>{"description"=>"the new password for the account when changing the password", "example"=>"newpassword", "readOnly"=>true, "type"=>["string"]}, "password"=>{"description"=>"current password on the account", "example"=>"currentpassword", "readOnly"=>true, "type"=>["string"]}, "updated_at"=>{"description"=>"when account was updated", "example"=>"2012-01-01T
```

This truncates it down:

```
1.9.3-p194 :094 > api=PlatformAPI.connect("", "xxxxx")
 => #<Heroics::Client>
1.9.3-p194 :095 > 
```

Maybe there's a more useful description that can be outputted? Like, name of the schema or url of schema?