Provide hints to the btree layer Next and Previous primitives to let them 
know if they can be no-ops if the underlying index is unique.
Performance optimizations in sqlite3PcacheFetch().
Rearrange fields in the Parse object for a tighter packing, resulting in
an 8% size reduction on x64.
Remove the SF_Materialize flag from the SELECT object as it does not
accomplish anything useful.
Do not mark the ephemeral tables used to hold the RHS of IN clauses as
unordered because the NGQP will use those ephemeral tables to help order the
output.  This is not an issue for standard SQLite since ephemeral tables
there are always ordered, regardless of the hint.  It only affects systems
that substitute an alternative storage engine.
In the Win32 VFS, the winSysInfo variable should be static.
Add the ".repair" command to the command-line shell.
Rename the '.repair' shell command to '.clone'.
Add additional error messages and a progress spinner to the ".clone" command.
Change the spellfix1 virtual table to deterministically names its shadow
tables.
Delete the OP_VerifySchema opcode.  Enhance OP_Transaction to do the schema
version checks that OP_VerifySchema used to do.
Update comments in vdbe.c.  No changes to code.
More comment updates.  No changes to code.
Add the OP_Undef and OP_IsUndef opcodes.  With these, use the first register
in the result register range as the flag to indicate EOF on an INSERT from
a SELECT, rather than allocating a separate boolean register for that task.
Get rid of the OP_Undef and OP_IsUndef opcodes in favor of higher-level
OP_InitCoroutine and OP_EndCoroutine.
Change the OP_InitCoroutine instruction to jump over the co-routine
implementation.
In the TCL bindings, make sure Tcl_AppendResult() is always terminated
by "(char*)0" and not just "0".
Fix redundant definitions of _LARGE_FILE and _LARGEFILE_SOURCE.
Add opcodes OP_InitCoroutine and OP_EndCoroutine.  Use these to remove the
need for separate boolean registers to record when a co-routine has finished.
Change the OP_Trace opcode to OP_Init and give it the ability to jump to the
initialization code at the bottom of the program, thus avoiding the need for
an extra OP_Goto.