Create a SANDESH logger to log all C++ sandesh library errors/events. Set the
logging level of the SANDESH logger based on the --log-level argument/
configuration parameter. Changed C++ generated code to also use the right
logging level and the SANDESH logger. Changed argument "level" in 2 request
sandesh in sandesh_uve.sandesh since it was clashing with the base class
member.
Closes-Bug: #1379071

Change-Id: Ic263a76e32d648e4ca4c524247d67aa30af54751