Save commit: clear persistent device implemented
Save commit
Save commit: read_plog_t1 implemented

I am tired...

Signed-off-by: Akira Hayakawa <ruby.wktk@gmail.com>
Save commit: Haha, I am high!

Signed-off-by: Akira Hayakawa <ruby.wktk@gmail.com>
Save commit: implement rebuild_rambuf()

rebuild_rambuf() is to rebuild a rambuffer from a plog sequence
before replayin the log on the cache device we shall
flush out all the plogs on the persistent logging device.

writeboost.h is modified: add rebuild_rambuf()

care to refactor by relocating the functions;
logically unclear now.

Signed-off-by: Akira Hayakawa <ruby.wktk@gmail.com>
Compile OK

Signed-off-by: Akira Hayakawa <ruby.wktk@gmail.com>