upgraded requirement to Django 1.11.2, Pillow 4.1.1, PyYAML 3.12,...

upgraded requirement to Django 1.11.2, Pillow 4.1.1, PyYAML 3.12, django-tinymce 2.6.0 and python-dateutil 2.6.0

requirements.txt

-Django==1.10.7
+Django==1.11.2
 MySQL-python==1.2.5
-Pillow==3.3.0
-PyYAML==3.11
-django-tinymce==2.3.0
-python-dateutil==2.5.3
+Pillow==4.1.1
+PyYAML==3.12
+django-tinymce==2.6.0
+python-dateutil==2.6.0