Add experimental storyboard support

Most of the work comes from fluddokt, see itdelatrisu/opsu#480

src/clonewith/opsu/storyboard/SBComEventRunner.java

@@ -0,0 +1,34 @@
+package clonewith.opsu.storyboard;
+
+import java.util.List;
+import java.util.Set;
+
+/**
+ * Storyboard Command Event Runner
+ *
+ * @author fluddokt
+ *
+ */
+class SBComEventRunner extends SBEventRunner{
+	public int start = Integer.MAX_VALUE, end = Integer.MIN_VALUE;
+
+	public void addCommands(List<SBCommand> commands, Set<SBCommand> activeCommands) {
+		for(SBCommand c : commands) {
+			start = Math.min(start, c.startTime);
+			end = Math.max(end, c.endTime);
+			if(c.startTime == c.endTime || c.isSameInitalEndValue) {
+				if(c.isVarying)	//commands that vary just go to end value
+					events.add(new EndCommandSBEvent(c.startTime, c));
+				else	//commands that don't vary (flip/ blend) just sets it
+					events.add(new StartCommandSBEvent(c.startTime, c));
+
+			} else if(c.isVarying){
+				events.add(new AttachCommandSBEvent(c.startTime, activeCommands, c));
+				events.add(new RemoveCommandSBEvent(c.endTime, activeCommands, c));
+			} else {
+				events.add(new StartCommandSBEvent(c.startTime, c));
+				events.add(new EndCommandSBEvent(c.endTime, c));
+			}
+		}
+	}
+}