Make navigation structure more approachable to new users (#1083)

* Move event selector to sidebar

* Unify navigation

* Fix confusing icons

src/pretix/control/templates/pretixcontrol/vouchers/base.html

@@ -1,21 +0,0 @@
-{% extends "pretixcontrol/event/base.html" %}
-{% load i18n %}
-{% load bootstrap3 %}
-{% block title %}{% trans "Vouchers" %}{% endblock %}
-{% block content %}
-    <h1>{% trans "Vouchers" %}</h1>
-    <ul class="nav nav-pills">
-        <li {% if "event.vouchers" == url_name %}class="active"{% endif %}>
-            <a href="{% url 'control:event.vouchers' organizer=request.event.organizer.slug event=request.event.slug %}">
-                {% trans "All vouchers" %}
-            </a>
-        </li>
-        <li {% if "event.vouchers.tags" == url_name %}class="active"{% endif %}>
-            <a href="{% url 'control:event.vouchers.tags' organizer=request.event.organizer.slug event=request.event.slug %}">
-                {% trans "Tags" %}
-            </a>
-        </li>
-    </ul>
-    {% block inside %}
-    {% endblock %}
-{% endblock %}

src/pretix/control/templates/pretixcontrol/vouchers/bulk.html

@@ -4,7 +4,7 @@
 {% load bootstrap3 %}
 {% block title %}{% trans "Voucher" %}{% endblock %}
 {% block inside %}
-    <h1>{% trans "Create multiple voucher" %}</h1>
+    <h1>{% trans "Create multiple vouchers" %}</h1>
     <form action="" method="post" class="form-horizontal">
         {% csrf_token %}
         {% bootstrap_form_errors form %}

src/pretix/control/templates/pretixcontrol/vouchers/index.html

@@ -1,9 +1,10 @@
-{% extends "pretixcontrol/vouchers/base.html" %}
+{% extends "pretixcontrol/event/base.html" %}
 {% load i18n %}
 {% load bootstrap3 %}
 {% load urlreplace %}
 {% block title %}{% trans "Vouchers" %}{% endblock %}
-{% block inside %}
+{% block content %}
+    <h1>{% trans "Vouchers" %}</h1>
     <p>
         {% blocktrans trimmed %}
             Vouchers allow you to assign tickets to specific persons for a lower price. They also enable you to

src/pretix/control/templates/pretixcontrol/vouchers/tags.html

@@ -1,6 +1,8 @@
-{% extends "pretixcontrol/vouchers/base.html" %}
+{% extends "pretixcontrol/event/base.html" %}
 {% load i18n %}
-{% block inside %}
+{% block title %}{% trans "Voucher tags" %}{% endblock %}
+{% block content %}
+    <h1>{% trans "Voucher tags" %}</h1>
     <p>
         {% blocktrans trimmed %}
             If you add a "tag" to a voucher, you can here see statistics on their usage.