Revision 38221

From Gerri:
Few fixes to improve/reduce verbosity in case of connection broken or
reset by peer
- In TSocket:
  - Add bit  kBrokenConn and set it when the connection is broken or reset
    by peer
  - Add missing checks of return codes from Send and Recv operations
  - In CreateAuthSocket, add an optional argument to extract the error code
    in case of failure; set the error to kErrConnectionRefused when the
    failure is due to a broken or reset by peer connection.
- In TPSocket:
  - Add bit  kBrokenConn and set it when the connection is broken or reset
    by peer
  - Add missing checks of return codes from Send and Recv operations
  - In the main constructor, fix a bug causing a double connection attempt
    in case of failure
- In TNetFile:
  - Extract a more correct error code via CreateAuthSocket instead of
    setting the generic authentication error code
  - Fix a typo in a error message
- In TNetSystem:
  - Fix a bug in ConsistentWith causing always a new helper (and connection)
    instance to be created when repeating the request with the same path.