Extensive additions and fixes

Added

• Added missing jsonapi:authorizer generator command.
• The Eloquent schema now has indexQuery and relatableQuery methods. These allow filtering for authorization purposes when a list of resources is being retrieved. For instance, it could filter those queries so that only models belonging to the authenticated user are returned.
• #23 The resource request class now does not need to exist for the destroy controller action. Previously the implementation was expecting the resource request class to exist, even though delete validation was optional.
• #24 Controller actions will now stop executing and return a response if one is returned by the before action hooks: i.e. searching, reading, saving, creating, updating, deleting, readingRelated<Name>, reading<Name>, updating<Name>, attaching<Name> and detaching<Name>.
• #37 Can now use constructor dependency injection in Server classes.
• #40 There is now a new MetaResponse class that can be used when returning meta-only responses. In addition, response classes have been updated to add a withServer method. This can be used to specify the named server the response should use to encode the JSON:API document. This has to be used when returning responses from routes that have not run the JSON:API middleware (i.e. there is no default server available via the service container).
• #9 The Laravel route registrar is now passed through to the resources, relationships and actions callbacks as the second function argument.
• #36 Eloquent schemas now support complex singular filter logic, via the Schema::isSingular() method.
• #33 Specification compliance will now reject an incorrect resource type in a relationship. For example, if a relationship expects tags but the client sends posts, the request will be rejected with an error message that posts are not supported.

Changed

• #22 BREAKING The index and store methods on the authorizer contract now receive the model class as their second argument. This is useful for authorizers that are used for multiple resource types.
• BREAKING When querying or modifying models via the schema repository or store, calls to using() must be replaced with withRequest(). This change was made to make it clearer that the request class can be passed into query builders.
• #28 The sparse field sets validation rule will now reject with a specific message identifying any resource types in the parameter that do not exist.
• #35 The Relation::type() method must now be used when setting the inverse resource type for the relation.

Fixed

• Optional parameters to generator commands that require values now work correctly. Previously these were incorrectly set up as optional parameters that expected no values.
• #25 The encoder now correctly handles conditional fields when iterating over a resource's relationships.
• #26 Fix parsing the fields query parameter to field set value objects.
• #34 Do not require server option when generating a generic authorizer with multiple servers present.
• #29 Do not reject delete requests without a Content-Type header.
• #11 Fixed iterating over an empty to-many generator twice in the underlying compound document encoder.

Deprecated

• The Relation::inverseType() method is deprecated and will be removed in 1.0-stable. Use Relation::type() instead.