evolve: document the "if not shouldupdate" block
I missed the "not" in "if not shouldupdate: ... hg.updaterepo()" and
it took a long time for me to realize it's about updating *back* to
the original commit (or to its successor). Let's add a comment to
maybe help the person not make the same mistake.
-------------------------
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