Clarify precedence for template/style in commands.show_changeset():
Display format will be the first non-empty hit of:
1. option 'template'
2. option 'style'
3. [ui] setting 'logtemplate'
4. [ui] setting 'style'
If all of these values are either the unset or the empty string,
regular display via changeset_printer() is done.
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
abort: Permission denied: test-ro-message/b/vehicle