tests/test-basic.out

Move commands.forget over to using new walk code.

With no names, it now recursively forgets everything, as is the default
behaviour of other commands.  And prints the names of all files it
hasn't specifically been told to forget.

+ mkdir t
+ cd t
+ hg init
+ echo a
+ hg add a
+ hg commit -m test -d '0 0'
+ hg history
changeset:   0:acb14030fe0a
tag:         tip
user:        test
date:        Thu Jan  1 00:00:00 1970
summary:     test

+ hg manifest
b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3 644 a
+ hg cat a
a
+ hg verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
1 files, 1 changesets, 1 total revisions