rename .html templates to .jinja2 for more consistency

templates/uploadinfo.html

@@ -1,23 +0,0 @@
-{% extends "base.html" %}
-
-{% block title %}Info on file "{{ upl.name }}" - {{ app_name }}{% endblock %}
-
-{% block content %}
-<h1>Info on file "{{ upl.name }}"</h1>
-
-<div class="upload-frame">
-  <img src="{{ upl.url }}" alt="{{ upl.name }}">
-</div>
-
-<p>You can include this file in other pages with <strong>{{ '{{' }}media:{{ upl.id }}{{ '}}' }}</strong>.</p>
-
-<h2>File info</h2>
-
-<p>Type: {{ type_list[upl.filetype] }}</p>
-
-<p>Upload ID: {{ upl.id }}</p>
-
-<p>Uploaded on: {{ upl.upload_date.strftime('%B %-d, %Y %H:%M:%S') }}</p>
-
-<p>Size: {{ upl.filesize }} bytes</p>
-{% endblock %}