Ruby 2.4 deprecation warning

[traviskroberts]

The ezcrypto dependency is causing the following deprecation warning:

warning: constant OpenSSL::Cipher::Cipher is deprecated

It appears that Ruby 2.4 changed OpenSSL::Cipher::Cipher.new() to just OpenSSL::Cipher.new(). There's a related issue open on the ezcrypto repo, but it looks like it might be abandonware at this point.