v3.2.0

• Update support to Laravel Framework v5.2.
• Use Orchestra\Contracts\Authorization\Authorizable contract.
• Remove default morphClass properties.
• Only hash password (using mutator) when rehashing is required.
• Add Orchestra\Model\Observer\Role::saving() to disable adding "Guest" as a role.
• Add Orchestra\Model\Traits\OwnedByTrait.
• Add Orchestra\Model\Traits\OwnsTrait.
• Refactor Orchestra\Model\Observer\Role::updating().
• Add Orchestra\Model\Plugins\RefreshOnCreate.
• Allow customizing searchable fields/attributes via Orchestra\Model\User::$searchable.
• Add Orchestra\Model\Eloquent::transaction() method to execute model using transaction.