Fixes to the `cache` Jinja tag. * Thread safety, since it stores common data potentially coming from pages baked at the same time. * Correctly capture and restore modifications made to the execution context (e.g. sources used in the captured section).

@echo off
setlocal

set CUR_DIR=%~dp0
set CHEF=%CUR_DIR%..\bin\chef
set OUT_DIR=%CUR_DIR%..\piecrust\res\messages
set ROOT_DIR=%CUR_DIR%messages

%CHEF% --root=%ROOT_DIR% bake -o %OUT_DIR%
del %OUT_DIR%\index.html