GameMode Timer

v beta 2.0
Added configs (per world) and the associated commands (i.e. /gmt [config option] [world] [value]) for:

• players - limit the number of players allowed to teleport to the world, if set to -1, this setting is ignored
• set_morning - if true sets the worlds time to 0 ticks when the first player joins
• keep_night - if true makes it always night from the time the game mode is switched until the last player leaves