Update GCS and App Engine Libraries

Update GCS Library to version 0.4.3 and App Engine to 1.9.17
Update timeouts used with the GCS Library.

Change-Id: I818185e39d8207365339be8d1fd2789a1e9318d6
Modify the Buildserver shutdown system

Modify the buildserver shutdown system to accept a delay
parameter. This parameter, specified in seconds, defines a grace
period between now and the specified time in the future. During the
grace period the health check function will return “unhealthy” while
the buildserver itself will continue to accept new jobs. This more
gracefully handles the time period between then we declare that we
want to shutdown the buildserver and when the load balancer finally
decides that this buildserver is truly unhealthy (which requires
several polls) and takes it out of service. During this grace period
any jobs given to the buildserver by the load balancer will still be
honored.

Change-Id: Icf9f3f5cf7c958ee57ed774ab6a27457e6b347dc
Merge branch 'master' of github.com:mit-cml/appinventor-sources
Restore project
Adds Join test app.
Send message
Implements available, adds text received event, refactor.
Send message done
Updates join.aia
Triggers text received in UIThread.
Adds unable to write error.
Refactor for sending/receiving msgs
Implements device name, address, status in WifiDirect.
Refactors the wifidirect component. Adds base class for groupowner and client.
Fixes error in odemessages
Adds wifidirect group owner as a new component.
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