move interact trait up one level to InteractiveShellApp

IPython/core/shellapp.py

@@ -198,6 +198,8 b' class InteractiveShellApp(Configurable):'
     )
     shell = Instance('IPython.core.interactiveshell.InteractiveShellABC',
                      allow_none=True)
+    # whether interact-loop should start
+    interact = Bool(True)
     
     user_ns = Instance(dict, args=None, allow_none=True)
     def _user_ns_changed(self, name, old, new):

IPython/terminal/ipapp.py

@@ -272,7 +272,6 b' class TerminalIPythonApp(BaseIPythonApplication, InteractiveShellApp):'
     _module_to_run_changed = _file_to_run_changed
 
     # internal, not-configurable
-    interact=Bool(True)
     something_to_run=Bool(False)
 
     def parse_command_line(self, argv=None):