obslog: make changeset available to templater
obslog templating currently has very limited support for templating
the precursor changeset (when available). The only available keywords
are {node}, {rev}, and {shortdescription}. This patch makes the entire
changeset available to the templater by passing it to
formatter.context(). That function has been available since Mercurial
4.2.
syntax: re
/figures/[^/]+\.png$
^html/
\.pyc$
~$
\.swp$
\.orig$
\.rej$
^tests/.*\.err$
^tests/easy_run.sh$
^build/
^dist/
^MANIFEST$
^docs/tutorials/.*\.rst$
\.ico$
tests/\.testtimes
^docs/training/graphs/
^docs/training/html/
^docs/training/index.html
^docs/training/graphviz-images/
^docs/training/img/
^docs/training/output/
^docs/training/pandocfilters/