Appengine-python-standard

This version includes an update to the NDB package - the `msgprop` module was added to provide back-compatibility with App Engine first generation.

Additionally, an internal package was added to support this module - `google.appengine._internal.protorpc`.

Update the Memcache SDK with 'peek' methods to fetch item timestamps.

Limiting use of deprecated package - imp for python3.x

Update the Search SDK to enable listing indexes in all namespaces.

Add ndb support for compatible py27/py3 memcache entity caching.

Update README to include `google.appengine.api.search`.