Update #6: Design tweaks, terrain types, infinite mode

Gameplay:

• Player speed increases on the pavement and decreases on the grass
• No more ten day limit, survive as long as you can
• Amount of people increases more slowly
• Amount of initial infected eventually increases
• removed timer

Design:

• Iterated over the level design
• Tweaked colors, lighting, and camera
• added fog, and floating particles
• tweaked ground for new walkway object
• added more decorations