fix return values of commands (#124)

src/Bundle/Command/BaseServerCommand.php

@@ -32,7 +32,7 @@ protected function execute(InputInterface $input, OutputInterface $output)
     {
         $this->getCommand($input)->execute($this->getCommandOptions($input));
 
-        return 1;
+        return 0;
     }
 
     /**

src/Bundle/Command/CheckCommand.php

@@ -75,7 +75,7 @@ protected function execute(InputInterface $input, OutputInterface $output)
 
         $io->writeln('');
 
-        return 1;
+        return 0;
     }
 
     /**

src/Bundle/Command/FetchCommand.php

@@ -92,7 +92,7 @@ protected function execute(InputInterface $input, OutputInterface $output)
             $storage->fetch($file);
         }
 
-        return 1;
+        return 0;
     }
 
     /**

src/Bundle/Command/PushCommand.php

@@ -46,7 +46,7 @@ protected function execute(InputInterface $input, OutputInterface $output)
             $storage->push($file);
         }
 
-        return 1;
+        return 0;
     }
 
     /**

src/Bundle/Command/SelfUpdateCommand.php

@@ -42,7 +42,7 @@ protected function execute(InputInterface $input, OutputInterface $output)
             $output->writeln('You are already using "' . $updater->getNewVersion() . '" version.');
 
             // No update needed!
-            return 1;
+            return 0;
         }
 
         $upgradeFile = 'phar://' . $updater->getLocalPharFile() . '/UPGRADE.md';
@@ -53,7 +53,7 @@ protected function execute(InputInterface $input, OutputInterface $output)
 
         $output->writeln(sprintf('Updated from %s to %s', $updater->getOldVersion(), $updater->getNewVersion()));
 
-        return 1;
+        return 0;
     }
 
     /**