Added Wolf creature interface

By: Dinnerbone <dinnerbone@dinnerbone.com>

paper-api/src/main/java/org/bukkit/entity/Wolf.java

@@ -0,0 +1,35 @@
+
+package org.bukkit.entity;
+
+/**
+ * Represents a Wolf
+ */
+public interface Wolf extends Animals {
+    /**
+     * Checks if this wolf is angry
+     *
+     * @return Anger true if angry
+     */
+    public boolean isAngry();
+
+    /**
+     * Sets the anger of this wolf
+     *
+     * @param angry true if angry
+     */
+    public void setAngry(boolean angry);
+
+    /**
+     * Checks if this wolf is sitting
+     *
+     * @return true if sitting
+     */
+    public boolean isSitting();
+
+    /**
+     * Sets if this wolf is sitting
+     *
+     * @param sitting true if sitting
+     */
+    public void setSitting(boolean sitting);
+}