core: get rid of `pickle`: Use of `pickle` to serialise data was a technical legacy that was causing trouble to store in database, to update (if a class was serialised, a change could break update), and to security (pickle can lead to code execution). This patch remove all use of Pickle in favour in JSON, notably: - for caching data, a Pydantic model is now used instead - for SQLAlchemy model, the LegacyPickle is replaced by JSON serialisation - in XEP-0373 a class `PublicKeyMetadata` was serialised. New method `from_dict` and `to_dict` method have been implemented to do serialisation. - new methods to (de)serialise data can now be specified with Identity data types. It is notably used to (de)serialise `path` of avatars. A migration script has been created to convert data (for upgrade or downgrade), with special care for XEP-0373 case. Depending of size of database, this migration script can be long to run. rel 443

@ECHO OFF

pushd %~dp0

REM Command file for Sphinx documentation

if "%SPHINXBUILD%" == "" (
	set SPHINXBUILD=sphinx-build
)
set SOURCEDIR=.
set BUILDDIR=.build

if "%1" == "" goto help

%SPHINXBUILD% >NUL 2>NUL
if errorlevel 9009 (
	echo.
	echo.The 'sphinx-build' command was not found. Make sure you have Sphinx
	echo.installed, then set the SPHINXBUILD environment variable to point
	echo.to the full path of the 'sphinx-build' executable. Alternatively you
	echo.may add the Sphinx directory to PATH.
	echo.
	echo.If you don't have Sphinx installed, grab it from
	echo.http://sphinx-doc.org/
	exit /b 1
)

%SPHINXBUILD% -M %1 %SOURCEDIR% %BUILDDIR% %SPHINXOPTS%
goto end

:help
%SPHINXBUILD% -M help %SOURCEDIR% %BUILDDIR% %SPHINXOPTS%

:end
popd