Replay simulation

[hungrymonkey]

First commit.

I have to fix lots of things such as

the stimulation start on game start which is wrong. It should start on button press.

the damn writer keep writing 'pre_start_game' function

some of the method calls are pretty broken

[hungrymonkey]

the score broken was due to saving the player id as string and the score expected an int.

No need to fix in the commit. Its gdscript problem

{"os_time":1519168280,"p_name":{"1":"The Warrior","1284942386":"The Warrior"},"spawn_points":{"1":0,"1284942386":1}}