obsexchange: make compatible with some unreleased 4.5 versions We don't generally care to be compatible with unreleased versions of hg, but this is just a one-line change to be compatible with a range of commits before 158d4ecc03c8 (wireprotoserver: move all wire protocol handling logic out of hgweb, 2018-03-08), so hopefull it can be worth it.

compat: make override of createmarkers work on wrapped function If createmarkers() has been wrapped using functools.partial(), the __code__ attribute won't exist. Fix by unwrapping partial functions. I tried to find another attribute to use as proxy for the "__code__.co_argcount < 6", but there were no new functions or similar added in that commit.

previous/next: add -m short form for --merge This matches core's option to `hg update`. This patch also covers `hg next`, but test-check-commit.t only lets me mention one of them.