public function getIndex()
 {
     $expenseAll = Expense::orderBy('id', 'DESC')->paginate(15);
     $expense = new Expense();
     $allInvoices = $expense->getExpenseInvoiceDropDown();
     $invoice = Input::get('invoice_id');
     $expenseInvoice = Expense::where('invoice_id', $invoice)->get();
     return view('Expenses.list', compact('expenseAll'))->with('allInvoices', $allInvoices)->with('expenseInvoice', $expenseInvoice);
 }