SDK-778: Update Django required version to prevent compatibility issue with Python 3.7+

Author: echarrod

examples/yoti_example_django/requirements.in

@@ -1,4 +1,4 @@
 yoti>=2.5.0
-Django==1.11
+Django>1.11.16
 python-dotenv>=0.7.1
 django-sslserver

examples/yoti_example_django/requirements.txt

@@ -11,7 +11,7 @@ cffi==1.11.5              # via cryptography
 chardet==3.0.4            # via requests
 cryptography==2.2.2       # via pyopenssl, yoti
 django-sslserver==0.20
-django==1.11
+django==2.1.7
 future==0.16.0            # via yoti
 idna==2.7                 # via cryptography, requests
 protobuf==3.6.0           # via yoti

setup.py

@@ -20,7 +20,8 @@
     install_requires=['cryptography>=2.2.1', 'protobuf>=3.1.0',
                       'requests>=2.11.1', 'future>=0.11.0', 'asn1==2.2.0', 'pyopenssl>=18.0.0'],
     extras_require={
-        'examples': ['Django>=1.8', 'Flask>=0.10', 'python-dotenv>=0.7.1', 'django-sslserver>=0.2', 'Werkzeug==0.11.15'],
+        'examples': ['Django>1.11.16', 'Flask>=0.10', 'python-dotenv>=0.7.1', 'django-sslserver>=0.2',
+                     'Werkzeug==0.11.15'],
     },
     classifiers=[
         'Development Status :: 5 - Production/Stable',