Log

* adds modal_generic.html template for generic usage
* adds M2M field log to BaseObject
* adds show log button to controls.html
* adds logging on adding related objects
* adds render log table using generic modal
* adds tooltip to missing values in detail views
* adds/updates translations

templates/log.html

@@ -0,0 +1,33 @@
+{% load i18n %}
+<div class="table-container scroll-300">
+    <table class="table table-hover">
+        <thead>
+            <tr>
+                <th scope="col">
+                    {% trans 'Timestamp' %}
+                </th>
+                <th scope="col">
+                    {% trans 'Action' %}
+                </th>
+                <th scope="col">
+                    {% trans 'User' %}
+                </th>
+            </tr>
+        </thead>
+        <tbody>
+        {% for entry in log %}
+            <tr>
+                <td>
+                    {{entry.timestamp}}
+                </td>
+                <td>
+                    {{ entry.action_humanize}}
+                </td>
+                <td>
+                    {{entry.user}}
+                </td>
+            </tr>
+        {% endfor %}
+        </tbody>
+    </table>
+</div>

templates/modal/modal_generic.html

@@ -0,0 +1,17 @@
+{% load i18n l10n %}
+{% comment %}
+    A generic modal template which is derived from modal_form.html on django-bootstrap-modal-forms package
+    https://pypi.org/project/django-bootstrap-modal-forms/
+{% endcomment %}
+
+
+<div class="modal-header">
+    <h5 class="modal-title">{{ modal_title }}</h5>
+    <button type="button" class="close" data-dismiss="modal" aria-label="Close">
+        <span aria-hidden="true">&times;</span>
+    </button>
+</div>
+
+<div class="modal-body">
+    {% include modal_body_template %}
+</div>