Generate hashCode()/equals(): Support deep array equality

#KT-19102 Fixed

idea/testData/codeInsight/generate/equalsWithHashCode/nestedArray.kt.after

@@ -0,0 +1,18 @@
+import java.util.Arrays
+
+class EqKotlin(val a: Array<Array<String>>) {
+    <caret>override fun equals(other: Any?): Boolean {
+        if (this === other) return true
+        if (javaClass != other?.javaClass) return false
+
+        other as EqKotlin
+
+        if (!Arrays.deepEquals(a, other.a)) return false
+
+        return true
+    }
+
+    override fun hashCode(): Int {
+        return Arrays.deepHashCode(a)
+    }
+}