Added web ui with templates

templates/rules_new.html

@@ -0,0 +1,36 @@
+{% extends "base.html" %}
+{% block title %}Create rule{% endblock title %}
+{% block body %}
+  <form action="/rules/new" method="post" class="flex flex-col">
+    <label class="grow">
+      Description
+      <input type="text" name="description" />
+    </label>
+    <label class="grow">
+      Regex
+      <input type="text" name="regex" />
+    </label>
+    <label class="grow">
+      Category
+      <select name="category">
+        <option></option>
+        {% for cat in categories %}
+        <option value={{cat.category_id}}>{{cat.name}}</option>
+        {% endfor %}
+      </select>
+    </label>
+    <button type="submit">Submit</button>
+  </form>
+  <style>
+    label {
+      width: 100%;
+    }
+
+    input {
+      width: 100%;
+      border: 1px solid black;
+      border-radius: 3px;
+      padding: 0.25rem;
+      margin: 0.25rem;
+}
+{% endblock body %}