Clear config.log file during game startup

[lent1-andrealphusgames]

When config.log is defined, this file is opened in append mode.
The log file will grow endlessly if not manually cleared/deleted.

It would be great if you can add a config variable to open the file in write mode.
It should wipe the content of the log file each time the game starts

I'm thinking of something like that:
in config.rpy

# A logfile that logging messages are sent to.
log = None

# Clear config.log at startup
clear_log = False

and in export.py

if not logfile:
    import os
    if renpy.config.clear_log:
        file_mode = "w"
    else:
        file_mode = "a"
    logfile = open(os.path.join(renpy.config.basedir, renpy.config.log), file_mode)

So we can change the filemode through options.rpy with something like this:

define config.log = "game.log"
define config.clear_log = True

If that's not relevant, I'll continue to manually delete the log file.

Thanks