Add a fast path for getting bitmap values from a cursor.
Don't reset all LSM chunk cursors at the start of a search.

We're walking the cursors anyway: reset as we go.  This also has the advantage that we don't bump the session cursor count from zero to one at each level of the tree, so we don't repeatedly do a cache full check and update the snapshot.
Copyright exception for generated Python script.
lsm_cursor.c:847: 'c' may be used uninitialized in this function
Fix the "chunk_max" calculation: exclude chunks that will not be part of the merge.
whitespace