Rename field part.has_variants to part.is_template

InvenTree/part/templates/part/part_base.html

@@ -9,7 +9,7 @@
     This part is not active:
 </div>
 {% endif %}
-{% if part.has_variants %}
+{% if part.is_template %}
 <div class='alert alert-info alert-block'>
     This part is a <i>template part</i>.<br>
     It is not a <i>real</i> part, but real parts can be based on this template.

InvenTree/part/templates/part/tabs.html

@@ -2,7 +2,7 @@
     <li{% ifequal tab 'detail' %} class="active"{% endifequal %}>
         <a href="{% url 'part-detail' part.id %}">Details</a>
     </li>
-    {% if part.has_variants %}
+    {% if part.is_template %}
     <li{% ifequal tab 'variants' %} class='active'{% endifequal %}>
         <a href="{% url 'part-variants' part.id %}">Variants <span class='badge'>{{ part.variants.count }}</span></span></a>
     </li>
@@ -25,7 +25,7 @@
     <li{% ifequal tab 'used' %} class="active"{% endifequal %}>
         <a href="{% url 'part-used-in' part.id %}">Used In{% if part.used_in_count > 0 %}<span class="badge">{{ part.used_in_count }}</span>{% endif %}</a></li>
     {% endif %}
-    {% if part.purchaseable and part.has_variants == False %}
+    {% if part.purchaseable and part.is_template == False %}
     <li{% ifequal tab 'suppliers' %} class="active"{% endifequal %}>
         <a href="{% url 'part-suppliers' part.id %}">Suppliers
             <span class="badge">{{ part.supplier_count }}</span>

InvenTree/part/templates/part/variants.html

@@ -15,7 +15,7 @@
 
 <div id='button-toolbar'>
     <div class='btn-group'>
-        {% if part.has_variants and part.active %}
+        {% if part.is_template and part.active %}
         <button class='btn btn-success' id='new-variant' title='Create new variant'>New Variant</button>
         {% endif %}
     </div>