add InsufficientFundsException

src/main/kotlin/ltd/lulz/exception/InsufficientFundsException.kt

@@ -0,0 +1,10 @@
+package ltd.lulz.exception
+
+@Suppress("unused")
+class InsufficientFundsException : RuntimeException {
+
+    constructor() : super()
+    constructor(message: String?) : super(message)
+    constructor(message: String?, cause: Throwable?) : super(message, cause)
+    constructor(cause: Throwable?) : super(cause)
+}