Fix -Wunused-but-set-variable warning
Fix -Wunused-but-set-variable warning
Fix -Wunused-variable warning
Fix a few warnings
[YARP_OS/Log] Check arguments of the c-style debug functions

This ensures that the arguments supplied have types appropriate to the
format string specified, and that the conversions specified in the
format string make sense. On gcc the warning is enabled by -Wformat.
[YARP_OS/Log] Improve reading of debug environment variables

Trace is now disabled when debug is disabled
[YARP_OS/Log] Simplify print_callback and forward_callback implementations

Hopefully it will not impact performances
[YARP_OS/Log] Use the full name for colored_output variable in color macros
[YARP_OS/Log] Remove extra space in final forwarded output line
[YARP_OS/Log] Use ACE_OS::snprintf instead of sprintf
[YARP_OS/Log] Fix -Wformat-security warnings
[YARP_OS/Log] Remove no longer used variables
[yarplogger] Make trace light grey instead of purple
[yarplogger] Initialize QApplication after ResourceFinder

On linux, QApplication "eats" the --name argument
[yarplogger] Use ResourceFinder singleton instead of passing one around
[YARP_OS/Log] Refactor logging functions and add non forwarding macros
[YARP_OS/Log] Print thread id when verbose output is enabled
[YARP_OS/Log] Add "Component" logging macros
[YARP_logger] Parse component tag
[yarplogger] Show component in a separate column