OpenNebula

Some things that can be improved:

• RM does not log the user doing the request, or the important arguments, like the object id
• oneimage disable or delete simply says "Could not disable/delete image", when the reason is that the Image is in the USED state
• There are some operations, like a onevm stop, that log return codes in oned.log without loggin the operation that returned it: [TM][D]: Message received: LOG I 22 ExitCode: 0
• VirtualMachineManagerDriver.cc uses Log::ERROR to log successful actions
• Log::MessageType has up to 5 log levels, but Nebula::get_debug_level allows only up to 3