Fixes #35 - Corrected lag_time to 0.03 (above 0.018)

Edited hook.py and corrected to PEP8 standard, cleaned obsolete variables, etc.

lag_time was set to 30ms (0.03 seconds)

The marks were also corrected. If style12 line contains "B", this means that
black player should move, so last move was performed by white player.
Then, if "B" is received, "white_code" mark is sent.