[Tinyos-Storage WG] Support checkpointing / rollback for storage objects

[Prabal Dutta]

[From Gaurav Mathur's original e-mail]

Storage objects should be able to maintain state across system
resets/reboots (if the user wants). Rather than each object
maintaining its own state, it might be a better to develop a common
framework that can be used to store and retrieve object state to and
from flash.

Questions
* What should be the design of such a common framework that objects can re-use ?
* Should the implementation be platform dependent or independent ?