i18n: rework <h1> headings in changeset.html, eliminating embedded <py:if> directives (Genshi limitation, see #G372).
i18n: rework <h1> headings in changeset.html, eliminating embedded <py:if> directives (Genshi limitation, see #G372).

Fixes #9192.


git-svn-id: eda3d06fcef731589ace1b284159cead3416df9b@9422 af82e41b-90c4-0310-8c96-b1721e28e2e2

jun66j5/trac-ja,walty8/trac,jun66j5/trac-ja,walty8/trac,netjunki/trac-Pygit2,jun66j5/trac-ja,jun66j5/trac-ja,netjunki/trac-Pygit2,walty8/trac,netjunki/trac-Pygit2,walty8/trac