obshistory: omit duplicate notes of obsolescence operations When folding changesets, it's possible to provide a --note flag to e.g. fold or prune, which will store a note for that operation. But since there would be more than one marker for the fold operation and the provided note would be stored in all of them, _markersnotes() previously would return the same text message many times. We don't really want to see the same thing over and over, so let's make notes a set(). This will also make unrelated operations with the same note show the message only once, which is probably an improvement too.

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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