localrepo: push manifestlog and changelog construction code into store This feels substantially more appropriate, as the store is actually the layer with knowledge of how to handle this storage. I didn't move the caching decorators for now because that's going to require some more involved work, and this unblocks my current experimentation. Differential Revision: https://phab.mercurial-scm.org/D6732

notify: add option for deterministic message-id generation Copied from email by durin42: > Pierre-Yves asked offline why I asked a new option for this and why it > is not the default. Message-Id is supposed to be unique world-wide and > while it is desirable to have a deterministic mechanism for them for > creating follow-up emails, it needs organisational control for ensuring > the uniqueness. Differential Revision: https://phab.mercurial-scm.org/D6824

uncommit: add options to update to the current user or current date These are also from the evolve extension's version of uncommit. I tried adding validation that both forms of user or date can't be specified at the same time, but that fails because these show up in `opts` with a None value whether or not the option was given on the command line. Presumably that means the conditional in `resolvecommitoptions` could be simplified. But this is how both evolve and MQ handle it. Differential Revision: https://phab.mercurial-scm.org/D6828

uncommit: add support to modify the commit message and date Currently, the evolve extension's version of this command supports it. Differential Revision: https://phab.mercurial-scm.org/D6827

run-tests: add a dedicated 'isoptional' function This is clearer than repeated manual call to to 'endswith'. (This is a gratuitous cleanup that I made while investigating a bug).

run-tests: remove the artificial indentation