Add Expenses app

A UI based on [Budget Zen](https://github.com/BrunoBernardino/budgetzen-web) but slightly updated and adjusted for bewCloud. It also features a chart with available money and spent by budgets.

This is useful for envelope-based budgeting.

db-migrations/003-expenses-app.pgsql

@@ -0,0 +1,40 @@
+SET statement_timeout = 0;
+SET lock_timeout = 0;
+SET idle_in_transaction_session_timeout = 0;
+SET client_encoding = 'UTF8';
+SET standard_conforming_strings = on;
+SELECT pg_catalog.set_config('search_path', '', false);
+SET check_function_bodies = false;
+SET xmloption = content;
+SET client_min_messages = warning;
+SET row_security = off;
+
+CREATE TABLE public.bewcloud_budgets (
+    id uuid DEFAULT gen_random_uuid(),
+    user_id uuid DEFAULT gen_random_uuid(),
+    name text NOT NULL,
+    month character varying NOT NULL,
+    value numeric NOT NULL,
+    extra jsonb NOT NULL,
+    created_at timestamp with time zone DEFAULT now()
+);
+
+ALTER TABLE ONLY public.bewcloud_budgets ADD CONSTRAINT bewcloud_budgets_pkey PRIMARY KEY (id);
+ALTER TABLE ONLY public.bewcloud_budgets ADD CONSTRAINT bewcloud_budgets_user_id_fkey FOREIGN KEY (user_id) REFERENCES public.bewcloud_users(id);
+ALTER TABLE ONLY public.bewcloud_budgets ADD CONSTRAINT bewcloud_budgets_user_id_name_month_unique UNIQUE (user_id, name, month);
+
+
+CREATE TABLE public.bewcloud_expenses (
+    id uuid DEFAULT gen_random_uuid(),
+    user_id uuid DEFAULT gen_random_uuid(),
+    cost numeric NOT NULL,
+    description text NOT NULL,
+    budget text NOT NULL,
+    date character varying NOT NULL,
+    is_recurring boolean NOT NULL,
+    extra jsonb NOT NULL,
+    created_at timestamp with time zone DEFAULT now()
+);
+
+ALTER TABLE ONLY public.bewcloud_expenses ADD CONSTRAINT bewcloud_expenses_pkey PRIMARY KEY (id);
+ALTER TABLE ONLY public.bewcloud_expenses ADD CONSTRAINT bewcloud_expenses_user_id_fkey FOREIGN KEY (user_id) REFERENCES public.bewcloud_users(id);