Partition logic fixed to
 -handle case of write() buffer len > partition size
 -handle case of write(byte) tripping over partition
 -final partition being 0 bytes long
 -close open output stream of final block
BUG: not all FileSystem entry points made sure paths were absolute before passing down to the store
add a test for uploads of >10 partitions
more partition logic. But delete? delete may be broken