Minor variable rename/tweak.

Signed-off-by: crynobone <crynobone@gmail.com>
Add Orchestra\Extension\Contracts\FactoryInterface.

Signed-off-by: crynobone <crynobone@gmail.com>
Merge branch '2.1' into 2.2

Conflicts:
	src/Extension/Factory.php
Small tweaks.

Signed-off-by: crynobone <crynobone@gmail.com>
Add Orchestra\Extension\Contracts\RouteGeneratorInterface

Signed-off-by: crynobone <crynobone@gmail.com>
utilize Illuminate\Support\Collection.

Signed-off-by: crynobone <crynobone@gmail.com>
Add Orchestra\Extension\Contracts\PublisherInterface

Signed-off-by: crynobone <crynobone@gmail.com>
Merge branch '2.2'