Update from GMS 1.4 to the new GameMaker

This update brings a few new features compared to the oldest versions:

• New Weapons:
  • MP5 cost 1500 fast firing speed and high damage for earlier waves
  • M4A1 cost 2500 fast firing assault rifle with high damage for later waves
• Bugfixes with damage, collision with zombies and buying items (You  can now buy items while having the exact amount of money)
• Improved the button layout in the menu
• Added an intro scene for the first night only.
• Balanced the damage that zombies deal to the base
• You can lose now!