Update 0.3.1

Changes in this version:

• Increased the possible pause between pirate invasions 90s => 180s
• Pirates now only chase SSF, tankers and traders
• Highway trader multi-initialize fix
• Changed price for space parts 3 => 6
• Fixed buy fuel faulty button state 
• Players now can't split unowned items in the market
• Show market item price
• Show technology price + research time
• Buy fuel window fixes