Fix return types for Archive::getStream

Signed-off-by: Morris Jobke <hey@morrisjobke.de>

lib/private/Archive/Archive.php

@@ -113,7 +113,7 @@ abstract class Archive {
 	 * get a file handler
 	 * @param string $path
 	 * @param string $mode
-	 * @return resource
+	 * @return bool|resource
 	 */
 	abstract public function getStream($path, $mode);
 	/**

lib/private/Archive/TAR.php

@@ -339,7 +339,7 @@ class TAR extends Archive {
 	 *
 	 * @param string $path
 	 * @param string $mode
-	 * @return resource
+	 * @return bool|resource
 	 */
 	public function getStream($path, $mode) {
 		if (strrpos($path, '.') !== false) {

lib/private/Archive/ZIP.php

@@ -187,7 +187,7 @@ class ZIP extends Archive {
 	 * get a file handler
 	 * @param string $path
 	 * @param string $mode
-	 * @return resource
+	 * @return bool|resource
 	 */
 	public function getStream($path, $mode) {
 		if ($mode == 'r' or $mode == 'rb') {