Upgrade twisted to 20.3.0

requirements.txt

@@ -1,5 +1,5 @@
 asn1crypto==0.24.0
-attrs==17.4.0
+attrs==19.3.0
 autobahn==18.3.1
 Automat==0.6.0
 baseplate==0.30.6
@@ -38,19 +38,21 @@ pyasn1-modules==0.2.1
 pycparser==2.18
 pycrypto==2.6.1
 pycurl==7.19.3
+PyHamcrest==1.10.1
 pyinotify==0.9.4
 PyJWT==1.7.1
 pyOpenSSL==17.5.0
 pyserial==2.6
-pytz>=2018.9
+pytz==2019.3
 PyYAML==5.3.1
 requests==2.23.0
-service-identity==17.0.0
+service-identity==18.1.0
 six==1.11.0
 SQLAlchemy==1.3.0
 thrift==0.13.0
-Twisted==16.1.0
+Twisted==20.3.0
 txaio==2.9.0
 urllib3==1.25.8
+webencodings==0.5.1
 Werkzeug==0.14.1
 zope.interface==4.4.3