Add a missing '#include "tcl.h"' to test_rtree.c.
Improve performance of sqlite3VdbeRecordCompare() by using an approximation
that might give false negatives and only running the more expensive exact 
subexpression if the approximation fails.
Factor all KeyInfo object allocations into a single function:
sqlite3KeyInfoAlloc().  Always allocate enough space so that 
sqlite3VdbeRecordCompare() can avoid checking boundaries and hence
run faster.
For the vtshim module, always zero out the xChildDestroy function pointer after calling it.
Performance optimization: Avoid calling convertCompoundSelecctToSubquery()
on queries that do not use the UNION, EXCEPT, or INTERSECT operators.
More than double the speed of the resolveP2Values() routine in vdbeaux.c by
moving from an extended if-else on every opcode to a switch.  Opcodes are
reordered in mkopcodesh.awk to put the switched opcodes close together,
for additional performance and to reduce code footprint.
Clean up the input reader in the command-line shell for improved legibility
and performance.
For the ".import" command of the command-line shell, start a transaction
if there is not one active already.
Remove unreachable branches in expr.c, replacing them with assert() and
testcase() statements.
Add a testcase() macro to verify OOM coverage.
Update the configure script to use the latest version number (3.8.0).
Adjust #ifdefs in test_autoext.c so that it compiles with 
SQLITE_OMIT_LOAD_EXTENSION.  Fix compiler warnings in two other
test modules.  No changes to the core.
Fix a test case related to partial indices so that it works even if
STAT3 is disabled.
Fix typos and add clarification to comments in where.c.  No code changes.
Add a guard #ifndef to test_intarray.h to prevent harm if it is #included
more than once.  Add a comment on the closing #endif of the guards on
sqlite3.h and test_multiplex.h.
When estimating the number of rows scanned using data from the sqlite_stat4 table, avoid allocating UnpackedRecord and KeyInfo structures until they are definitely required.
Remove the unused sqlite3Utf8to16() utility function.
Fix the ".dump" command on the command-line shell so that it works for
"sqlite_stat4" in addition to "sqlite_stat1".
Change the way samples for the sqlite_stat4 table are collected.
Fix typos in a comment in analyze.c. No code changes.