support nested repositories.
mercurial will not recurse into a subdirectory that contains a .hg
directory. it is treated as a separate repository.
%%% should show a removed and b added
A b
R a
reverting...
saving current version of b as b.orig
forgetting b
undeleting a
%%% should show b unknown and a back to normal
? b
? b.orig
merging a
%%% should show foo-b
foo-b
%%% should show a removed and b added
A b
R a
? b.orig
reverting...
forgetting b
undeleting a
%%% should show b unknown and a marked modified (merged)
? b
? b.orig
%%% should show foo-b
foo-b