Fix a typo in a requirements mark comment.  No changes to code.
Version 3.8.1
In the vfslog extension for FILECONTROL records, show the pragma name for
SQLITE_FCNTL_PRAGMAs and the requested size for SQLITE_FCNTL_SIZE_HINT.
Further enhance the vfslog extension to record the number of freelist pages
and the first freelist page in CHNGCTR-READ and CHNGCTR-WRITE records.
Add the SQLITE_FCNTL_TRACE file control and generate it for OP_Trace
when compiled with SQLITE_USE_FCNTL_TRACE.  Update vfslog.c to make
use of the new file control.  Also update vfslog.c to log UNLOCK events
before the fact, rather than afterwards.
Fix a bug causing an "malformed database schema error" error if a temp table with the same name as an existing table that has at least one temp trigger attached to it is created.
Improved header comment with better instructions on the vfslog.c
extension.
Improve support for the SQLITE_OMIT_FLAG_PRAGMAS compile-time option.
Add the ".open" command to the command-line shell.
Improved "wheretrace" capabilities:  Show the constraint expression if the
wheretrace flag has the 0x100 bit set and if compiled with
SQLITE_ENABLE_TREE_EXPLAIN.
Bug fix and enhancements to the improved wheretrace logic that shows the
constraint expressions.
More wheretrace debugging support:  Show a listing of all WHERE clause
terms (on wheretrace bit 0x100) and include important flags such as
TERM_VIRTUAL, WO_EQUIV, and EP_FromJoin.
Do not use transitive WHERE-clause constraints on LEFT JOINs.
Fix for ticket [c620261b5b5dc].
Add regression tests for ticket [c620261b5b5].
Formatting improvements to the WHERE-clause constraint display in the
wheretrace debugging logic.
Merge all trunk changes since 3.8.1 into the sessions branch.