Clarify variable naming and purpose

Author: APickledWalrus

src/main/java/ch/njol/skript/aliases/ItemType.java

@@ -211,7 +211,7 @@ public void setTo(ItemType i) {
 		for (final ItemData d : i) {
 			types.add(d.clone());
 		}
-		isRandom = i.isRandom;
+		isWrappingItemStack = i.isWrappingItemStack;
 	}
 
 	public ItemType(Block block) {
@@ -670,7 +670,11 @@ public ItemType clone() {
 
 	private final static Random random = new Random();
 
-	public boolean isRandom = false;
+	/**
+	 * Represents whether this ItemType is simply wrapping an ItemStack.
+	 * That is, it has only a single data, and that data represents a random ItemStack.
+	 */
+	public boolean isWrappingItemStack = false;
 
 	/**
 	 * @return One random ItemStack that this ItemType represents. If you have a List or an Inventory, use {@link #addTo(Inventory)} or {@link #addTo(List)} respectively.
@@ -683,7 +687,7 @@ public ItemType clone() {
 	 * @see #removeFrom(List...)
 	 */
 	public @Nullable ItemStack getRandom() {
-		if (isRandom) {
+		if (isWrappingItemStack) {
 			ItemStack stack = types.getFirst().getStack();
 			stack.setAmount(getAmount());
 			return stack;

src/main/java/org/skriptlang/skript/bukkit/types/ItemTypeClassInfo.java

@@ -67,7 +67,7 @@ private static class ItemTypeParser extends Parser<ItemType> {
 		public @Nullable ItemType parse(String s, ParseContext context) {
 			ItemType itemType = Aliases.parseItemType(s);
 			if (itemType != null && itemType.getTypes().size() == 1 && itemType.getTypes().getFirst().getStack() != null) {
-				itemType.isRandom = true;
+				itemType.isWrappingItemStack = true;
 			}
 			return itemType;
 		}