mode=copy should not copy unversioned files (and use VC-specific commands)

[Almad]

mode=copy should use VC-specific commands, archieving higher speed and consuming less HDD space.

This, however, require change of behavior and not expect to copy unversioned files.

See  maillist discussion.

This ticket should modify tests to add+commit files which are now only touched.

Then, ticket for each VC backend should be specified. It's already implemented for hg in #263

[Almad]

I'll modify tests to add+commit touched files.

If it's decided to write "thou should not copy unversioned files", I hope someone will help with it ,)

[dustin]

See #669.