More description about checks

Signed-off-by: Michal Čihař <michal@cihar.com>

weblate/html/checks.html

@@ -30,6 +30,7 @@
   <div class="panel-heading"><h4 class="panel-title">{% trans "Information" %}</h4></div>
   <div class="panel-body">
   <p>{% trans "Customizable quality checks will help you in improving quality of translations." %}</p>
+  <p>{% trans "The checks can help you identify problematic translations or source strings which are hard to translate." %}</p>
   </div>
   <div class="panel-footer">
   <a class="btn btn-default" href="{% documentation 'user/checks' %}">{% trans "Documentation" %}</a>