client: xtfsutil_server: Removed "using namespace xtreemfs::pbrpc;" since this...

client: xtfsutil_server: Removed "using namespace xtreemfs::pbrpc;" since this lead to name clashes with the system's "stat" type.

git-svn-id: https://xtreemfs.googlecode.com/svn/trunk@3579 f8528748-c2c0-11dd-ba5c-d3b7c2b3b534