Fix Issue #139, rolled back TX should not throw exception on close.
Fix Issue #139, rolled back TX should not throw exception on close.

mebigfatguy/mapdb,cocosli/mapdb,hangum/mapdb,binarytemple/mapdb,ringoluo/mapdb,olupas/MapDB,pettermahlen/mapdb,SleimanJneidi/mapdb,olupas/MapDB,jankotek/MapDB,lamfire/mapdb,jankotek/mapdb,ffjiao/mapdb,sumit784/mapdb,jankotek/mapdb,mebigfatguy/mapdb,morfeo8marc/mapdb,jankotek/MapDB,codeaudit/mapdb