Add Modifiers class to modify speed

[Sean-Nishi]

Modifiers class will include: Info

• who gave/owns the modifier
• what the modifer does
• explain finer details (on timer, how to get rid of, maybe stacking buff) Vars modifier: int
• the modifier const timer: int
• how long the modifier lasts (in seconds) same_buff_count: int
• if a stacking buff (can get the same buff multiple times), keep track of the number of times to account for this buff Methods operation->int
• operations include (+-*%/) and will be truncated to an int