Rework the logic that factors constant expressions out of inner loops, making
it both simpler and faster.
Merge EXPLAIN fixes from trunk.
Simplify the range scan code generate while also avoiding an unnecessary
OP_Affinity opcode.
Improvements to the Expr comparison routine to make it more general.
Improvements to unary-minus code generation so that it can make use of
a global constant register with a zero value.
Add test cases for INSERT INTO ... DEFAULT VALUES on tables with numeric
constants in CHECK constraints.
Changes to make the new constant expression factoring logic more general
and more testable.
Merge the operator comment fixes from trunk.
Add ALWAYS and NEVER macros to currently unreachable but important branches in
sqlite3ExprCompare().
Fix testcase misc7-16 so that it works with the new UNIQUE constraint error
message format.
Simplification and performance improvement to the logic that factors 
constant expressions ouf of inner loops.
Avoid unnecessary OP_IfNull checks when doing a range query where there
is a constraint on the lower bound of the range.
Fully constraint the ORDER BY on the top-10 line of the --summary output
from the wordcount test program.  Add the run-wordcount.bash script for
running wordcount in various configurations.