Rename the 'form' block to 'visible_fields' for consistency (and accuracy)

wagtail/wagtailadmin/templates/wagtailadmin/generic/create.html

@@ -16,7 +16,7 @@
 
         <div class="nice-padding">
             <ul class="fields">
-                {% block form %}
+                {% block visible_fields %}
                     {% for field in form.visible_fields %}
                         {% include "wagtailadmin/shared/field_as_li.html" %}
                     {% endfor %}

wagtail/wagtailadmin/templates/wagtailadmin/generic/edit.html

@@ -16,12 +16,12 @@
             {% endblock %}
 
             <ul class="fields">
-                {% block form %}
+                {% block visible_fields %}
                     {% for field in form.visible_fields %}
                         {% include "wagtailadmin/shared/field_as_li.html" %}
                     {% endfor %}
                 {% endblock %}
-                
+
                 <li>
                     <input type="submit" value="{% trans 'Save' %}" />
                     {% if can_delete %}