Write some better selection test cases to test new Iterate_fast func.

If not resuming, don't crash on badly written checkpoint_data.

If don't recover hardlink support and hardlink support on, don't
resume.

Fix crash that can occur when exception is found in the middle of a
file (duplicate by backing up /proc remotely).  (John Goerzen)

Copy sockets (Mickey Everts)


---------[ Long term ]---------------------------------------

Think about adding Gaudet's idea for keeping track of renamed files.

Look into different inode generation techniques (see treescan, Dean
Gaudet's other post).