Add public/private key encryption to the crypto functions

Idea created by nickorr on Jan 14, 2018

    The extensions of the curl functions in 16 made almost all Web Services available using native HTTP functions.  However, some websites using various implementations of Oauth ( 1.0 and 2.0 ) utilise public/private key pairs for encryption and identification.


    Examples include Xero which does OAuth 1.0 and requires OAuth of the form :


    openssl dgst -sha1 -sign privatekey.pem -binary


    Also some google services :


    Using OAuth 2.0 for Server to Server Applications  |  Google Identity Platform  |  Google Developers


    But I've seen plenty of other service.  On top of that public/private key crypto would be valuable generally across a wide range of other potential services.


    I'd like to see FileMaker extend the functions built into to allow encryption using the key and decryption using the matched key pair.  As well, we'd need a function to be able to do one time generation of key pairs. 


    There's example code of this in the BaseElements plugin open source repository where it uses this for a Xero authentication, and key creation function.