spearmint: Expose control of more bot trace contentmasks to Game VM

Also expose pass entity num for AAS_DropToFloor.

To maintain the same behavior in game VM;
  - AAS_DropToFloor: Use passent 0, contentmask CONTENTS_SOLID
  - Others: Use contentmask CONTENTS_SOLID|CONTENTS_PLAYERCLIP
spearmint: Fix reconnecting bot at map change

Before it use to run ClientBegin for playernum based on bot clientnum.
It was wrong when there were splitscreen players added before bot was added.