py3: fix sorting of obsolete markers when building bundle
Last item of marker tuple (parents) is either None or tuple. Comparison
thus fails on Python 3 with:
TypeError: '<' not supported between instances of 'tuple' and 'NoneType'
Fixing this by coercing None to the empty tuple when sorting markers in
exchange._getbundleobsmarkerpart().
Pierre-Yves David <pierre-yves.david@octobus.net> [Thu, 10 Oct 2019 04:34:58 +0200] rev 43167
sidedata: rename the configuration option to `exp-use-side-data`
We don't want setup configured to use the final version that would end using the
experimental one while using and older version.
Differential Revision: https://phab.mercurial-scm.org/D7040