Changed team names/icons to Katanas and Sais

These were the default team names in Turtle Arena 0.2. Red was changed to Foot in TA 0.4. TA 0.6 used Shell and Clover (which were meant for EBX).
Update CTF flag skins for new default team icons
Changed Neutral CTF flag skin to use shuriken

Previously used an EBX player icon.