server: libxtreemfs for Java: Fixed bug in async write code. Pending writes...

server: libxtreemfs for Java: Fixed bug in async write code. Pending writes were not decreased if the file size did not change.

git-svn-id: https://xtreemfs.googlecode.com/svn/trunk@3550 f8528748-c2c0-11dd-ba5c-d3b7c2b3b534