evolve: introduce a resolutionparent variable and store it in evolvestate
This patch introduces a resolutionparent variable which will be the parent of
final changeset after resolving content-divergent changesets.
Till now, the parent is always the parent of one of the divergent node, but now
in upcoming cases, it can be a successor of both the parents of divergent nodes.
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Evolve Commands Reference
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.. highlight:: none
amend
-----
.. hghelp:: amend
evolve
------
.. hghelp:: evolve
fold
----
.. hghelp:: fold
metaedit
--------
.. hghelp:: metaedit
next
----
.. hghelp:: next
obslog
------
.. hghelp:: obslog
pdiff
-----
.. hghelp:: pdiff
previous
--------
.. hghelp:: previous
prune
-----
.. hghelp:: prune
pstatus
-------
.. hghelp:: pstatus
split
-----
.. hghelp:: split
touch
-----
.. hghelp:: touch
uncommit
--------
.. hghelp:: uncommit