Sharing: add Sender data to share by email

This makes conversations a bit easier, since users can now reply to a shared email
It also removes the default
From: WordPress <WordPress@domain.com>

modules/sharedaddy/sharedaddy.php

@@ -15,7 +15,9 @@ function sharing_email_send_post( $data ) {
 	$content .= $data['post']->post_title."\n";
 	$content .= get_permalink( $data['post']->ID )."\n";
 
-	wp_mail( $data['target'], '['.__( 'Shared Post', 'jetpack' ).'] '.$data['post']->post_title, $content );
+	$headers[] = sprintf( 'From: %1$s <%2$s>', $data['name'], $data['source'] );
+
+	wp_mail( $data['target'], '['.__( 'Shared Post', 'jetpack' ).'] '.$data['post']->post_title, $content, $headers );
 }
 
 function sharing_add_meta_box() {
@@ -148,4 +150,4 @@ function sharing_email_check( $true, $post, $data ) {
 if ( defined( 'RECAPTCHA_PRIVATE_KEY' ) ) {
 	add_action( 'sharing_email_dialog', 'sharing_email_dialog' );
 	add_filter( 'sharing_email_check', 'sharing_email_check', 10, 3 );
-}
+}