search page now returns matching parts

- Searches 'name' and 'description' field
- Uses the JSON API

InvenTree/templates/navbar.html

@@ -12,13 +12,7 @@
       <li><a href="{% url 'company-index' %}">Companies</a></li>
     </ul>
     <ul class="nav navbar-nav navbar-right">
-        <form class="navbar-form navbar-left" action="{% url 'search' %}" method='post'>
-            {% csrf_token %}
-            <div class="form-group">
-                <input type="text" name='search' class="form-control" placeholder="Search">
-            </div>
-            <button type="submit" id='search-submit' class="btn btn-default">Submit</button>
-        </form>
+        {% include "search_form.html" %}
     {% if user.is_authenticated %}
       <li class='dropdown'>
           <a class='dropdown-toggle' data-toggle='dropdown' href="#"><span class="glyphicon glyphicon-user"></span> <b>{{ user.get_username }}</b></a>