Mark missing files as '?', not '!'

Files that were deleted with `rm` instead of `hg rm` have status 'deleted'
instead of 'removed'.

Previously, deleted files were treated the same as removed files, and caused
the status/dirtiness marker to include '!'. After this commit, deleted files
are treated the same as unknown files, and cause the dirtiness marker to
include '?'.

Motivation: both 'deleted' and 'unknown' indicate working-directory-only
changes that will not be committed.
1 files changed, 4 insertions(+), 2 deletions(-)

M +4 -2
@@ 283,8 283,10 @@ def prompt(ui, repo, fs='', **opts):
         g = m.groups()
         st = repo.status(unknown=True)
-        modified = any((st.modified, st.added, st.removed, st.deleted))
-        unknown = len(st.unknown) > 0
+        # Deleted files are like unknown files: the removal happened in the
+        # working directory, but won't be committed unless `hg rm` is used.
+        modified = any((st.modified, st.added, st.removed))
+        unknown = any((st.unknown, st.deleted))
         flag = ''
         if '|modified' not in g and '|unknown' not in g: