Some custom particles don't render correctly

[RobertBeckebans]

Reported by several users. Probably a wrong bounding box because of

if( fileSystem->UsingResourceFiles() )
{
	bounds = idBounds( vec3_origin ).Expand( 8.0f );
	return true;
}```

int bool idDeclParticle::Parse( const char* text, const int textLength, bool allowBinaryVersion )