bug#65252: Renpy raises exception when opening save screen.

[Jesse Gibbons]

Here's a problem I diagnosed in the version of renpy installed by guix 
(19a7a824c35eae56ce56e2a460042fb7e2129234):
Problem: Save screen raises an exception
How to replicate:
1. launch a renpy project
2. Navigate to the save screen.
An exception is raised and the stack trace is dumped.
Cause: config.has_sync not set outside renpy/common/00sync.rpy which is 
deleted by guix (presumably for security reasons)
Proposed Solution: Set config.has_sync = None in a different file at a 
point while config.locked=False. If no suitable file can be found, 
perhaps create renpy/common/00guix.rpy using a patch?

--
-Jesse Gibbons