upgrade sqlite from 3.5.9 to 3.6.22

you should notice the following from the Android changes in 3.5.9
1. Android Changes are grouped wherever possible.

To Do
1. sqlite3_get_pager_stats() needs to be completed
2. Android change lines 63480-63482 on master branch in sqlite3.c is
not ported yet. can't see where it goes in 3.6.22 code.