Force editor to appear for an 'hg backout' if a message or logfile aren't
supplied. Pre-fill the commit message with the changeset being backed out.
Fixes bug 238.
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