Could someone please reviews this patch?
This patch includes the following changes.

1. Correct ambiguous words
  e.g. sample -> sampling
       sample -> cpu (in some context)
2. Introduce `profile' data structure (that was `log' data structure)
  `log' data structure is now pushed down to lower level.
3. Fix broken serialization/deserialization of profiles.
4. Change profiler-sampling-interval to 10 by default.
5. Introduce some new commands.
6. Rename some badly named commands

    Tomohiro