Large performance update

The performance of the game has been greatly increased, hopefully providing a greater experience for everyone.

There are also now flowers, grass and rocks along the terrain.

After a few more impovements i will move onto building destruction.

On my low end pc with a 750 ti fps went from 25 to 100 fps on lowest settings
And with a 1070 went from 60 to 130 on highest settings although now population size has the main affect on performance.

This update also takes down the game size by 1GB