add some output to explain the pre-conditions for decrypt-all

apps/encryption/lib/crypto/decryptall.php

@@ -84,6 +84,9 @@ class DecryptAll {
 		$recoveryKeyId = $this->keyManager->getRecoveryKeyId();
 
 		if (!empty($user)) {
+			$output->writeln('You can only decrypt the users files if you know');
+			$output->writeln('the users password or if he activated the recovery key.');
+			$output->writeln('');
 			$questionUseLoginPassword = new ConfirmationQuestion(
 				'Do you want to use the users login password to decrypt all files? (y/n) ',
 				false
@@ -98,6 +101,9 @@ class DecryptAll {
 				$user = $recoveryKeyId;
 			}
 		} else {
+			$output->writeln('You can only decrypt the files of all users if the');
+			$output->writeln('recovery key is enabled by the admin and activated by the users.');
+			$output->writeln('');
 			$user = $recoveryKeyId;
 		}
 

lib/private/encryption/decryptall.php

@@ -119,6 +119,9 @@ class DecryptAll {
 		foreach ($encryptionModules as $moduleDesc) {
 			/** @var IEncryptionModule $module */
 			$module = call_user_func($moduleDesc['callback']);
+			$this->output->writeln('');
+			$this->output->writeln('Prepare "' . $module->getDisplayName() . '"');
+			$this->output->writeln('');
 			if ($module->prepareDecryptAll($this->input, $this->output, $user) === false) {
 				$this->output->writeln('Module "' . $moduleDesc['displayName'] . '" does not support the functionality to decrypt all files again or the initialization of the module failed!');
 				return false;