evolve: add missing import (caught by pylint)

evolve: improve transaction related code to use the lock module Refactored some of the places where we are using locking in evolve to use the lock module and write less code. This should also fix a couple of bug where tr could be None at release time.

evolve: remove unused variables As suggested by pyflakes, remove 5 unused variables in the evolve module.

evolve: remove unused code in _evolveany remove some code that was doing nothing useful in _evolveany.

evove: remove unused imports Three imports where unused in the evolve module.

tests: ensure we keep capturing output In 3.4, output capture with bundle2 is disabled by default on local push.

inhibit: updating to a obsolete commit prints warning message We move the inhibition marker in the same wlock than the update operation, this clears the warning message. To make it work we display the warning message on lock release in evolve.

evolve: stop conditional wrapping of _checkinvalidmarkers We support down to Mercurial 3.3, all such version have this function.

evolve: stop conditional wrapping of _getbundleobsmarkerpart We support down to Mercurial 3.3, all such version have this function.

evolve: stop conditional wrapping of _pushdiscoveryobsmarkers We support down to Mercurial 3.3, all such version have this function.

merge with stable

test-inhibit: test bookmark -D without prune enabled The --config option were dropped for lack of documentation.

inhibit: fix devel warning _inhibitmarkers was taking a transaction without the proper lock. Adding the lock removes the warnings.

evolve: add -i flag to amend command The -i flag was missing because it is not a global flag of the commit command. We can't make it a global flag yet as it is used in many places where it would not be appropriate so we just add it for this occurrence. Also, we only want to add it when commit supports it (otherwise it wouldn't work with older versions of mercurial)