Demo 1.3.1 hotfix

Hello everyone!

This is a small hotfix that fixes the issues that came up during the release of the 1.3.0 demo:

• Fixed that the intro video started again in case the loading has not been finished till the end of the video.
  
• The intro sound volume is now governed by the effect sound volume, not the music sound volume, which should make it louder by default.
  
• Fixed a crash that can happen when opening the smith projects when there is no approvable project in the list.
  
• Fixed a crash when the player successfully finishes the last mission.
  
• Aimed shot bow skill range is now correctly set to sight range from half-sight range.
  
• Added a general description for units from the Eastern culture.