Rename the devtools library: pylib -> devtoolslib.

mojo/devtools/common/pylib/shell.py

-# Copyright 2015 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-
-class Shell(object):
-  """Represents an abstract Mojo shell."""
-
-  def Run(self, arguments):
-    """Runs the shell with given arguments until shell exits, passing the stdout
-    mingled with stderr produced by the shell onto the stdout.
-
-    Returns:
-      Exit code retured by the shell or None if the exit code cannot be
-      retrieved.
-    """
-    raise NotImplementedError()
-
-  def RunAndGetOutput(self, arguments):
-    """Runs the shell with given arguments until shell exits and returns the
-    output.
-
-    Args:
-      arguments: list of arguments for the shell
-
-    Returns:
-      A tuple of (return_code, output). |return_code| is the exit code returned
-      by the shell or None if the exit code cannot be retrieved. |output| is the
-      stdout mingled with the stderr produced by the shell.
-    """
-    raise NotImplementedError()