Bumped some secondary requirements

The cryptography package was getting old, and since Flamenco is going to
issue JWT tokens soon, I wanted to be up to date with security fixes.

Also requires updating pillar-python-sdk.

requirements.txt

@@ -42,9 +42,9 @@ asn1crypto==0.24.0
 Babel==2.6.0
 billiard==3.5.0.4
 Cerberus==1.2
-cffi==1.10.0
+cffi==1.12.2
 click==6.7
-cryptography==2.0.3
+cryptography==2.6.1
 Events==0.3
 future==0.16.0
 googleapis-common-protos==1.5.3
@@ -61,14 +61,14 @@ protobuf==3.6.0
 protorpc==0.12.0
 pyasn1==0.4.4
 pyasn1-modules==0.2.2
-pycparser==2.17
+pycparser==2.19
 pymongo==3.7.0
 pyOpenSSL==16.2.0
 pytz==2018.5
 requests-oauthlib==1.0.0
 rsa==3.4.2
 simplejson==3.16.0
-six==1.10.0
+six==1.12.0
 urllib3==1.22
 vine==1.1.4
 webencodings==0.5.1