For one, this allows us to use MSG_DEBUG in order to emit debug
messages (requires -v processing).
As another effect, if the -C conffile option was given, there is no
need at all to run through all the process of looking up a system
config file - it's right there already.
Also, move it after the logfile creation if -l logfile was given, so
the respective debug message can go to the logfile.
* Find 'avrdude.conf' based on absolute path to executable
* Update coding style
* Update coding style
* Update 'src/doc/avrdude.texi' to reflect the new search method for 'avrdude.conf'
