* New exception class: lmdb.BadDbiError.
* Environment.copy() and Environment.copyfd() now support compact=True, to
trigger database compaction while copying.
* Various small documentation updates.
* CPython set_range_dup() and set_key_dup() both invoked MDB_GET_BOTH, however
set_range_dup() should have instead invoked MDB_GET_BOTH_RANGE. Fix by
Matthew Battifarano.
* lmdb.tool module was broken on Win32, since Win32 lacks signal.SIGWINCH. Fix
suggested by David Khess.