Fix confusing message from hg revert (
issue332)
% mkdir sub1
% touch sub1/file1
% hg add sub1/
adding sub1/file1
% hg rev sub1
sub1: No such file in rev
e4c586763258
forgetting sub1/file1
abort: repository a not found!
255
abort: error: Connection refused
255
abort: repository a not found!
255
abort: destination '../a' already exists
255
abort: repository a not found!
255
destination directory: q
abort: destination 'q' already exists