docs: add concepts guide (the set theory behind obsolescence)

docs: add guide to sharing mutable history

docs: add new user guide This has also been reviewed to death on evolve-testers. There are still a couple of short sections to write (clearly marked "TODO"), and one example to add. But (if I may be so bold) this is a gigantic improvement over the current docs, so it really should get merged. Incidentally, the figures are all SVG files created with Inkscape. They're not perfect, but they're pretty nice. Anyone who knows a better way to create technical diagrams is welcome to contribute. One wart: there's a test script that accompanies the document and largely duplicates it, but I haven't unified them. I've been concentrating on writing the best possible content, not on fiddling with tools. I suspect that unifying them will be non-trivial, but definitely worth doing.

docs: rewrite index page (including dangling links to future docs) This has been reviewed to death on the evolve-testers mailing list. I've made some minor tweaks since the last round of reviews, but the main content is the same.

amend: add -D/--current-date option, just like mq's qrefresh has Carefully designed so we can easily add -D to other changeset-creating commands (probably anything that takes -d), and so that we can add -U/--current-user as well. When that's done, the date and user options should be very similar to those in MQ.

amend: explicitly test -d option

amend: in tests, do not rely on defaults -- always use explicit -d Having a default -d option will make it hard to test -D/--current-date, which is coming shortly: presence of -d overrides -D, just like with mq's qrefresh.

evolve: fix createmarkers() wrapper to accept an iterable Docstring in mercurial.obsolete says "<relations> must be an iterable of ...", and hgsubversion takes it at its word and passes a generator. Until around Mercurial 3.0, this did not cause any problems, but now it does: in a repo with both evolve and hgsubversion enabled, pushing to Subversion when obsolete changesets are present causes a crash: [...] File "/home/gward/src/hgsubversion/hgsubversion/wrappers.py", line 346, in push obsolete.createmarkers(repo, relations) File "/home/gward/src/hg-stable/mercurial/extensions.py", line 196, in wrap return wrapper(origfn, *args, **kwargs) File "/home/gward/src/hg-evolve/hgext/evolve.py", line 332, in _createmarkers relations[idx] = (prec, sucs, meta) TypeError: 'generator' object does not support item assignment Since hgsubersion is playing by the documented rules, evolve must be the guilty party here.

merge with 4.0.0

Added tag 4.0.0 for changeset 0304fc2bab15