Add optional 'author' field to wp plugin list (#369)

* Add `author` as an optional field to
`plugin list`

* Add test for author field

* Update test

Author: fmfernandes

features/plugin.feature

@@ -311,6 +311,12 @@ Feature: Manage WordPress plugins
       | name       | status   | file                |
       | akismet    | active   | akismet/akismet.php |
 
+    When I run `wp plugin list --status=active --field=author`
+    Then STDOUT should contain:
+      """
+      Automattic
+      """
+
   Scenario: List plugin by multiple statuses
     Given a WP multisite install
     And a wp-content/plugins/network-only.php file:

src/Plugin_Command.php

@@ -274,6 +274,7 @@ protected function get_all_items() {
 				'update_id'      => '',
 				'file'           => $name,
 				'auto_update'    => false,
+				'author'         => $item_data['Author'],
 			];
 		}
 
@@ -720,6 +721,7 @@ protected function get_item_list() {
 				'description'    => wordwrap( $details['Description'] ),
 				'file'           => $file,
 				'auto_update'    => in_array( $file, $auto_updates, true ),
+				'author'         => $details['Author'],
 			];
 
 			if ( null === $update_info ) {
@@ -1184,6 +1186,7 @@ public function delete( $args, $assoc_args = array() ) {
 	 * * description
 	 * * file
 	 * * auto_update
+	 * * author
 	 *
 	 * ## EXAMPLES
 	 *