Fixed action log so that two periods now do not occur in a row

Fixes #1290.

The bug was fixed in BMInterface->load_message_from_game_actions().

This pull request also includes a no-op refactor of BMGameAction->friendly_action_determine_initiative() based on Chaos' implication that implode() should be used.

http://jenkins.buttonweavers.com:8080/job/buttonmen-blackshadowshade/432/