client:

- Catch XtreemFSException in periodic xcap renewal and file size update
  threads which might be thrown when resolving an UUID.
- Added missing if check to LEVEL_WARN logging message.


git-svn-id: https://xtreemfs.googlecode.com/svn/trunk@3175 f8528748-c2c0-11dd-ba5c-d3b7c2b3b534