In the P4 column of the EXPLAIN listing, abbreviate "keyinfo" as just "k" and
"BINARY" as just "B".
Make sure KeyInfo objects on multi-column indices of WITHOUT ROWID tables
have the correct nField and nXField values.  Also, add the
SQLITE_ENABLE_MODULE_COMMENT compile-time option and the VdbeModuleComment()
macro and use it to label entry and exit points of some key routines.
Continue working to get UPDATE operational for WITHOUT ROWID tables.
Fix PRAGMA integrity_check so that it works on WITHOUT ROWID tables.