Make a test for #1572.  This test causes the assertion reported by kayak to fail in the old code, but doesn't fail in the new code.
{{{
log.c:1125 toku_txn_note_brt: Assertion `(TOKUTXN)txnv==txn' failed
}}}
Fixes #1572.


git-svn-id: file:///svn/toku/tokudb@10416 c7de825b-a66e-492c-adef-691d508d4ae1