Added secure urllib3 python requirement

Cruz Monrreal · web-flow · commit c89147ea3001 · 2018-08-29T16:21:15.000-05:00
This pulls in additional packages requiured for SSL verification for Py2 Ref: https://urllib3.readthedocs.io/en/latest/user-guide.html#ssl-py2
diff --git a/requirements.txt b/requirements.txt
@@ -16,4 +16,5 @@ jsonschema>=2.6
 future>=0.16.0
 six>=1.11.0
 git+https://github.com/armmbed/manifest-tool.git@v1.4.5
+urllib3[secure]
 mbed-cloud-sdk==2.0.0
