Initial requirement:New configuration backend for samba 3 SoC

[Ming]

Proposed requirement:
*Basic parameter access
	+++Other parts can easily use the interface to access essential parameter
               -The system should maintain essential parameter
               - The system should return correct value or give error
code with read access
               - With write access, the system should expose values to
some checking
                    if it's legal.
	+++Should not introduce much overhead
	+++Should change when file/database changed
			- The system should check it file/database modified
			- The system should parse file
			- The system should re-fill in-ram parameters
	++ Concurrent set access doesn't corrupt the value
			- When use TDB, it's provided by database.
         + Then system support transaction so web configure can
complete or totally fail
             without corrupt the integration
*Storage backend
	+++Should be compatible with smb.conf
	 ++TDB/LDB are supported
	  +Format convert between different storage
(Note: +++ most important,+ not important)
The requirements are not clear as I thought since identifying the new
configuration's properties may change as things go on. It mainly
describes what it should like more than how it should be done. I don't
know if it's suitable for a SoC term. Some requirement like
transactions is a long term thing.