Update to patched version of leveldb supporting reverse iterators.
Update to patched version of leveldb supporting reverse iterators.

permazen/permazen,archiecobbs/jsimpledb,permazen/permazen,tempbottle/jsimpledb,archiecobbs/jsimpledb,tempbottle/jsimpledb,tempbottle/jsimpledb,permazen/permazen,archiecobbs/jsimpledb