Fix emeralds, tokens, etc not resetting when restarting marathon mode in first level

I was watching LunickTMM's all emeralds attempts when he accidentally discovered that special stage tokens would not reset when restarting marathon mode in the first level. In case there's a campaign where you could collect emeralds in the first level, they reset now too. Update: Added a bunch of other things to reset like lives, score, continues... copied from G_InitNew function (Left out some netgame only stuff and starposts as well.). The reason I neglect ultimate mode is that you couldn't reset even if you had more than 1 life left. Apologies for my ignorance in the first commit.