Check for user home directory while installing requirements.

Fix infinite rebooting, if user doesn't have home directory.

bazarr/init.py

@@ -53,6 +53,9 @@ if not args.no_update:
             import pip
         except ImportError:
             logging.info('BAZARR unable to install requirements (pip not installed).')
+        else:
+            if os.path.expanduser("~") == '/':
+                logging.info('BAZARR unable to install requirements (user without home directory).')
             else:
                 logging.info('BAZARR installing requirements...')
                 subprocess.call([sys.executable, '-m', 'pip', 'install', '--user', '-r',