Moves some classes to the new container package, and improves some code

src/main/java/net/knarcraft/stargate/container/RelativeBlockVector.java

@@ -0,0 +1,75 @@
+package net.knarcraft.stargate.container;
+
+/**
+ * This stores a block location as a vector relative to a position
+ *
+ * <p>A relative block vector stores a vector relative to some origin. The origin in this plugin is usually the
+ * top-left block of a gate (top-left when looking at the side with the sign). The right is therefore the distance
+ * from the top-left corner towards the top-right corner. Depth is the distance from the top-left corner to the
+ * bottom-left corner. Distance is the distance outward from the gate.</p>
+ */
+public class RelativeBlockVector {
+
+    private final int right;
+    private final int depth;
+    private final int distance;
+
+    /**
+     * Instantiates a new relative block vector
+     *
+     * @param right    <p>The distance to the right relative to the origin</p>
+     * @param depth    <p>The distance downward relative to the origin</p>
+     * @param distance <p>The distance outward relative to the origin</p>
+     */
+    public RelativeBlockVector(int right, int depth, int distance) {
+        this.right = right;
+        this.depth = depth;
+        this.distance = distance;
+    }
+
+    /**
+     * Gets the distance to the right relative to the origin
+     *
+     * @return The distance to the right relative to the origin
+     */
+    public int getRight() {
+        return right;
+    }
+
+    /**
+     * Gets the distance downward relative to the origin
+     *
+     * @return The distance downward relative to the origin
+     */
+    public int getDepth() {
+        return depth;
+    }
+
+    /**
+     * Gets the distance outward relative to the origin
+     *
+     * @return The distance outward relative to the origin
+     */
+    public int getDistance() {
+        return distance;
+    }
+
+    @Override
+    public String toString() {
+        return String.format("(right = %d, depth = %d, distance = %d)", right, depth, distance);
+    }
+
+    @Override
+    public boolean equals(Object other) {
+        if (other == this) {
+            return true;
+        }
+        if (other == null || this.getClass() != other.getClass()) {
+            return false;
+        }
+        RelativeBlockVector otherVector = (RelativeBlockVector) other;
+        return this.right == otherVector.right && this.depth == otherVector.depth &&
+                this.distance == otherVector.distance;
+    }
+
+}