TTS -V0.11 (Optimization)

I tried to make my prototype less laggy, so I reworked the AI of the zombies (that was the major probleme in the performance)

Full list of addings and modifications :

- Modified the AI of the zombies for better performance

- Modified the way of how the player work (shoot and movement)

- Modified the way the time is calculated when you capture the point of interest

- Added blood effects when you shoot on zombies

- Added some sounds when you shoot and kill zombies

- Added an effect to the frequency tower to make it visible when it works

- Added an FPS counter on the top-left corner of the screen

However, I'm still working to make some optimization (specially in the AI of the companions)