fix autogen.sh (libtool installed by homebrew)

update .gitignore
move restore.c merger.c into mfsmaster/
use 1 as the first metaversion

mfsmetarestore use 0 as invalid version, let it work well
ignore reported chunks with id > nextchunkid

nextchunkid should not affected by behavior of chunk server,
or replaying changelogs will fail with "DATA MISMATCH"