Log cleanup

[set-soft]

• This patch changes the log mechanism.
  • Now we have different loggers for the submodules
  • The info is logged to stdout and other stuff to stderr
  • The debug, warning and errors has colors (also in the GUI)
  • The mechanism to avoid conflicts with the progress bar was simplified
  • The mechanism to redirect progress and logs in the GUI was simplified
• The code no longer uses print(), only the logging mechanism.
• All known errors/exceptions are redirected through KiCostError exception.
• We return different error levels according to the kind of error.
• Warnings now has codes to identify their kind.