cmdutil: use '[committemplate]' section like as map file for style definition Before this patch, each template definitions for 'changeset*' in '[committemplate]' section have to be written fully from scratch, even though many parts of them may be common. This patch uses '[committemplate]' section like as the map file for the style definition. All items other than 'changeset' can be referred from others. This can reduce total cost of template customization in '[committemplate]' section. When the commit template other than '[committemplate] changeset' is chosen by 'editform', putting '[committemplate] changeset' value into the cache of the templater causes unexpected result, because the templater stores the specified (= chosen) template definition into own cache as 'changeset' at construction time. This is the reason why '[committemplate] changeset' can't be referred from others.