client: Logging: In case of errors, the number of attempts and the information...

client: Logging: In case of errors, the number of attempts and the information if the error is final and thrown further will be logged.

git-svn-id: https://xtreemfs.googlecode.com/svn/trunk@2485 f8528748-c2c0-11dd-ba5c-d3b7c2b3b534