v1.02beta

Changelog:

• Display version in main score
• Better lego explosion
• supress errors due to model freed but present in LightMapGI
• better animation when hostage enters the post-office
• review of directory hierarchy and cleanup
• Refactoring UI
• Bugfix
  Helicopter not floating anymore when landed
• Bugfix
  Heli can now land where a tank has been just destroyed
• updated demo