don't use vcs _rev if rhodecode codes are not under version controll

rhodecode/__init__.py

@@ -31,6 +31,7 VERSION = (1, 3, 4, 'b')
 try:
     from rhodecode.lib import get_current_revision
     _rev = get_current_revision()
+    if _rev:
     VERSION += ('dev%s' % _rev[0],)
 except ImportError:
     pass