commit: select template by spec.ref name And load all templates defined in [committemplate] since the selected template is no longer be named as 'changeset'.

commit: do not look up committemplate in template paths (BC) From 5375ba75df40 and de5cee8ba088, I don't think the current behavior is intended. Commit templates should be processed as literal templates.

formatter: always store a literal template unnamed Now spec.ref should be '' if spec.tmpl is specified. Since spec.ref is the option to select the initial template to be rendered, it doesn't make sense to store the given literal template as spec.ref.

formatter: load templates section like a map file Since a map file has another level to select a template (spec -> mapfile -> topic), this isn't exactly the same as how a map file works. But I believe most users would expect the new behavior. A literal template is stored as an unnamed template so that it will never conflict with the templates defined in [templates] section.

test-command-template: rewrite recursion tests by using a map file A literal template will be unnamed soon, so no recursion will be practically made by using -T option.

templater: add simple interface for unnamed template (API) This provides a simpler API for callers which don't need full templating stack. Instead of storing the given template as the name specified by topic, use '' as the default template to be rendered.