Fix vended prompt_toolkit packages not beeing installed with pip

setup.py

@@ -13,7 +13,7 @@
 except ImportError:
  pass
 
-from setuptools import setup
+from setuptools import setup, find_packages
 from setuptools.command.sdist import sdist
 from setuptools.command.install import install
 from setuptools.command.develop import develop
@@ -341,8 +341,6 @@ def main():
  packages=[
  "xonsh",
  "xonsh.ply.ply",
- "xonsh.vended_ptk.prompt_toolkit",
- "xonsh.vended_ptk.wcwidth",
  "xonsh.ptk_shell",
  "xonsh.ptk2",
  "xonsh.parsers",
@@ -362,7 +360,7 @@ def main():
  },
  package_data={
  "xonsh": ["*.json", "*.githash"],
- "xonsh.vended_ptk": ["LICENSE-prompt-toolkit","LICENSE-wcwidth"],
+ "xonsh.vended_ptk": ["LICENSE-prompt-toolkit", "LICENSE-wcwidth"],
  "xontrib": ["*.xsh"],
  "xonsh.lib": ["*.xsh"],
  "xonsh.webconfig": [
@@ -375,6 +373,9 @@ def main():
  cmdclass=cmdclass,
  scripts=scripts,
  )
+ skw["packages"].extend(
+ ["xonsh.vended_ptk." + pkg for pkg in find_packages(where="xonsh/vended_ptk")]
+ )
  # We used to avoid setuptools 'console_scripts' due to startup performance
  # concerns which have since been resolved, so long as install is done
  # via `pip install .` and not `python setup.py install`.