Non-working preliminary implementation attempts on user authentication.
Add new APIs that take 64-bit length parameters:
sqlite3_malloc64(),
sqlite3_realloc64(),
sqlite3_bind_blob64(),
sqlite3_bind_texte64(),
sqlite3_result_blob64(),
and sqlite3_result_texte64().
Internal memory allocation routines also now use 64-bit unsigned length
parameters for safety.
Also add the sqlite3_msize() interface.
Fix the sqlite3_get_table() to use sqlite3_realloc64() to avoid a
integer overflow problem.
Add new interfaces to the loadable extension mechanism.
Change the name of the _texte64() interfaces to just _test64(), without the "e".
Further ideas on user authentication.  Not yet working code.
Add the ".user" shell command and implement the sqlite3_user_add()
routine.  Incremental check-in.  The code compiles but does not work.
Complete the implementation of the various APIs.  Fix several problems.
This is another incremental check-in that does not completely work.
Reorder parameters on the sqlite3_user_*() interfaces for consistency.
Add the first TCL test cases.
Add support for the extra parameter on the sqlite3_set_authorizer() callback
and support for failing an ATTACH with an authentication-required database
using bad credentials.  The extension is now feature complete, but much
testing and bug-fixing remains.
Move user authentication blocking from sqlite3_prepare() over to the
table lock generator, thus allowing SQL statements (like 
"PRAGMA locking_mode") that do not touch database content to run
prior to authentication.
Fix the sqlite3_user_change() interface so that it does allow a
non-admin user to change their own password.
Get the sqlite3_user_delete() interface working.
All interfaces working and tested.
Enhance the sqlite3_user_add() interface to initialize the user
authentication logic.  Add test cases for the extra argument on the
end of the authorizer callback.
Suppress the potential schema error that occurs when a non-user-auth
SQLite library tries to parse the sqlite_user table definition in a
user-auth database.
Clean up some #includes in the extension API implementation.
Add the SQLITE_USER_AUTHENTICATION extension to the trunk.  This extension
is disabled by default.  Special compilation procedures are need to enable
it.
Add new APIs that take 64-bit length parameters: sqlite3_malloc64(),
sqlite3_realloc64(), sqlite3_bind_blob64(), sqlite3_bind_text64(),
sqlite3_result_blob64(), and sqlite3_result_text64().
Add the sqlite3_msize() interface.
Internal memory allocation routines now use 64-bit unsigned
length parameters for safety.
Fix the sqlite3_get_table() to use sqlite3_realloc64() to avoid
a integer overflow problem.
Fix an issue with sqlite3_bind_text64() with the SQLITE_UTF16 encoding
parameter.  Remove some unreachable code from the text64() and blob64()
implementation.
Fix a problem with parser memory allocation on 32-bit systems.