convert: update the transplant, rebase and graft references in 'extra'

This change allows the origin() and destination() revsets to yield the same
results in the new and old repos after a conversion.  Previously, nothing would
be listed for queries in the new repo.

Like the SHA1 updates to the commit messages, this is only operational when the
'convert.hg.saverev=True' option is specified.  If the old reference cannot be
found, it is left as-is.  It seems slightly better to leave stale evidence of
the graft/transplant/rebase than to eliminate it entirely.

--HG--
extra : amend_source : a963270c01b911eef169dc9b366cf7e151353a51
cmdutil: better document command()

--HG--
extra : rebase_source : b6aa82933dc87e6e48dc40331d612ff425ae4f66
commands: add norepo argument to command decorator

Since decorators are evaluated at module load time and since the
@command decorator imports commands, the norepo variable (along with
its friends) may not be declared yet. These variables are now declared
before @command usage to ensure they are present.

--HG--
extra : rebase_source : 41ffa33341ad040ec0234cdf3b1d29ff3b3064c6
commands: define norepo in command decorator

--HG--
extra : rebase_source : 8b93aa18b1afc19472fb1bb7e1b67c8e704e99c4
convert: define norepo in command decorator

--HG--
extra : rebase_source : dbb8c7d05626210cd7433bbb88e05d34326c3b77
extra : amend_source : 1567ac3bc06d9012255a3c50be4154608cab74c2
largefiles: define norepo in command decorator

--HG--
extra : rebase_source : 46bd740f6561d7930bc37cc2fcc2320827bdc90e
extra : amend_source : 94366c4af93e9c364d42e7b1d683ef62c1dfd84d
mq: define norepo in command decorator

--HG--
extra : rebase_source : 1286b5717ba649486dd6152f88c653f00602c9a5
share: define norepo in command decorator

--HG--
extra : rebase_source : d391d33f5bf24c6c818ddc086d6d7a7885743b2c
extra : amend_source : f7558ea667f2fdc83cebcb114b782c01773bac56
tests: define norepo in command decorator

--HG--
extra : rebase_source : 8f5433d16a33b2497e91fad07cdad370fab0bbbb
cmdutil: add optionalrepo argument to command decorator

--HG--
extra : rebase_source : c69c688ca28bb8f3088e19dfb5bae48ed2d6b8dc
commands: define optionalrepo in command decorator

--HG--
extra : rebase_source : fa3cbf9b199b8644b9996eb0c41fdf9911cb8b5f
keyword: define optionalrepo in command decorator

--HG--
extra : rebase_source : 57172c98fdc3d882f3b1978a857c35b8a4290c5a
cmdutil: support inferrepo in command decorator

--HG--
extra : rebase_source : 6ff89da4b4ff283e2abc57a83dfec3e2e20c146f
commands: define inferrepo in command decorator

--HG--
extra : rebase_source : 56ef1b9cd825411fdb9d3771b3526cfdf549ee2a
churn: define inferrepo in command decorator

--HG--
extra : rebase_source : 76b17888b4b9ce5ae4be15ff307437f6e102c034
children: define inferrepo in command decorator

--HG--
extra : rebase_source : 88d5f8a6bb0ba1a0bd50e5810ae25a09f1384870
extra : amend_source : c5fce12bfea2424f244c62dcd4956cb287939580
extdiff: define inferrepo in command decorator

--HG--
extra : rebase_source : 5b7b8a77f43a5b0a912584fd7beff93b2d9ed769
graphlog: define inferrepo in command decorator

--HG--
extra : rebase_source : fa6080b56ec98dbe32001ae9cfa2c0e42f85d553
hgk: define inferrepo in command decorator

--HG--
extra : rebase_source : 05c455bac52b8c7370708f2a6a1d166248a16692
keyword: define inferrepo in command decorator

--HG--
extra : rebase_source : fb0386fc9f78f142b61612620569cc0fa82e6ede