Make txn->abort work without bombing out for {{{test_txn_abort5}}} one case. Fixes#431.
Start writing {{{test_txn_abort6}}}. Addresses #443.
Try to write a test for #399 and #400, but haven't managed to reproduce the problem. Addresses #399, #400.
Write a test for #332. Addresses #332.
git-svn-id: file:///svn/tokudb@2406 c7de825b-a66e-492c-adef-691d508d4ae1