BUGS

- Remove any occurence of "-o" flag un Compiler.py and RemoteJob.py
This will certainly imply some rewriting of the class

- When the temp_dir value of the paths section of the ompiler daemon
config file is set to a non existent directory, the config file file
seems to be ignored. For example, even if the lock_file_path value was
set to /tmp/dms.pid, the lock was created in the default lock file
path.  No error message was output to stderr or a log file.
The configuration system 

- The scheduler should handle a command to unsubscribe a compiler
daemon, and the compiler daemon should use it on exit.

- I launched a SchedulerDaemon and CompilerDaemon_mod. Then I launched 
a Monitor. I closed the Monitor and launched another one.
I wasn't able to click on the buttons of the last Monitor, the gui seemed to be 
frozen.
When I killed everything (SchedulerDaemon, CompilerDaemon_mod, Monitor) and 
relaunched them all, the Monitor worked.

- the methods that check configuration should return only a tuple, not
a tuple containing a tuple of erroneous keys and a return value,
because the last one is useless.

- The pid files are not removed upon program exit.

- In the cfg file of the CompilerDaemon, to specify 127.0.0.1 as the
scheduler address leads to the scheduler registering a compiler daemon
whose IP address is 127.0.0.1. When a compiler client ask for a
compiler daemon to do a job, the scheduler may answer by giving the ip
address 127.0.0.1, then the compiler client will query the compiler
daemon running on the same computer, which is bad. Indeed, the
compiler daemon whose config file contains 127.0.0.1 as scheduler IP
address won't do anything.