unshelve: don't commit unknown files during unshelve (
issue4113)
Previously, unshelve would temporarily commit unknown files (via addremove) in
an attempt to allow unshelving into unknown files. This produced unexpected
results, like the file time stamp changing and a .i file being created.
This change makes it no longer use addremove. It ignores unknown files
completely. If an unshelve would overwrite an unknown file, the unknown file is
moved to *.orig
The shelve continue/abort format is changed, but it just removes stuff from the
end of the file, so it can still read the old format.
'a' in d: True
d['a']: va
'b' in d: True
d['b']: vb
'c' in d: True
d['c']: vc
'd' in d: True
d['d']: vd
'a' in d: False
'b' in d: True
d['b']: vb
'c' in d: True
d['c']: vc
'd' in d: True
d['d']: vd
'e' in d: True
d['e']: ve
'b' in d: True
d['b']: vb2
'c' in d: True
d['c']: vc2
'd' in d: True
d['d']: vd
'e' in d: False
'f' in d: True
d['f']: vf
'b' in d: False
'c' in d: False
'd' in d: False
'e' in d: False
'f' in d: False