Add Gold item
Add sfx/animations to gold loot and set currency_id
Merge remote-tracking branch 'upstream/master' into currency

Conflicts:
	mods/alpha_demo/engine/misc.txt
Remove obsolete data from engine/loot.txt
Fix copy-paste error for coin animations
Merge pull request #324 from dorkster/currency

Gold as an item
Add gold icon artwork & increase gold stack max to 5000
Merge pull request #326 from dorkster/currency

Add gold icon artwork & increase gold stack max to 5000