bumped certifi requirements

requirements.txt

@@ -67,9 +67,9 @@ boto3==1.7.71 \
 botocore==1.10.71 \
     --hash=sha256:9302ad235db66efa9d11c664b1cb0b259826d82a206446460ea05bcfcc431a4a \
     --hash=sha256:ffa673c9a53f3ab4eba4ce8cf9d736177ca67509827e716cb5070f0b621fb0a7
-certifi==2018.8.13; python_version >= '3.0' \
-    --hash=sha256:4c1d68a1408dd090d2f3a869aa94c3947cc1d967821d1ed303208c9f41f0f2f4 \
-    --hash=sha256:b6e8b28b2b7e771a41ecdd12d4d43262ecab52adebbafa42c77d6b57fb6ad3a4
+certifi==2018.10.15 \
+    --hash=sha256:339dc09518b07e2fa7eda5450740925974815557727d6bd35d319c1524a04a4c \
+    --hash=sha256:6d58c986d22b038c8c0df30d639f23a3e6d172a05c3583e766f4c0b785c0986a
 cffi==1.11.5 \
     --hash=sha256:151b7eefd035c56b2b2e1eb9963c90c6302dc15fbd8c1c0a83a163ff2c7d7743 \
     --hash=sha256:1553d1e99f035ace1c0544050622b7bc963374a00c467edafac50ad7bd276aef \