Add support for PHP 7 by replacing mcrypt with openssl

[rielmedia]

Add support for PHP 7 by replacing mcrypt with openssl

[adamjudd]

@rielmedia,

Thanks for posting this issue ticket.

The mcrypt functions are currently just used for the import/export of plugin settings functionality found on the tools page.

As such - you should be fine to ignore the deprecation notices for now, but we'll definitely be working at updating the code to support the openssl equivalents so it can continue to work without issue in PHP 7.1+

[rielmedia]

Thanks for the quick response! Looking forward to the next update.

[i-make-robots]

FYI, do NOT attempt to install mcrypt by installing php5-dev alongside php7.2. It will break your php install as long as php5 is active. (oops.)