Add form for transactions

nummi/main/templates/main/transaction.html

@@ -1,4 +1,9 @@
-<h1>{{ transaction }}</h1>
+<form action="{% url 'update_transaction' transaction.id %}" method="post">
+	{% csrf_token %}
+	{{ form }}
+	<input type="submit" />
+</form>
+
 <ul>
 	{% for inv in invoices %}
 	<li><a href="{% url 'invoice' inv.id %}">{{ inv.name }}</a></li>