Log Message:
py-cryptography[_vectors]: updated to 2.4.1

2.4.1:
Fixed a build breakage in our manylinux1 wheels.

2.4:
BACKWARDS INCOMPATIBLE: Dropped support for LibreSSL 2.4.x.
Deprecated OpenSSL 1.0.1 support. OpenSSL 1.0.1 is no longer supported by the \ 
OpenSSL project. At this time there is no time table for dropping support, \ 
however we strongly encourage all users to upgrade or install cryptography from \ 
a wheel.
Added initial :doc:OCSP </x509/ocsp> support.
Added support for :class:~cryptography.x509.PrecertPoison.