r10232: Some work on ldb_sqlite3.

r10232: Some work on ldb_sqlite3.
It is still far from being usable in samba4 but I want to commit
so that the work does not get lost by mistake.
This is also a good way to get comments if somebody is interested.

Sorry Derrell I ended up rewriting large parts of the code but I find
this style much more readable. Thanks for the hard work done. Your
work was a good reference for me.

ah the current code also shows some good numbers

sqlite3 generic test:
uid search took 0.05 seconds
real    0m12.492s
user    0m0.492s
sys     0m0.345s

with tdb we still get better numbers:
uid search took 0.46 seconds
real    0m0.892s
user    0m0.360s
sys     0m0.468s

but most of the time is spent in adding operations and I think
there's still a lot of space for improvement.

Simo.
(This used to be commit ace9990060c10d0931f418934b2121aea9512ff7)