Switch Objective-PGP to RPGP

Objective-PGP is complicated. We might like to move to RPGP( https://github.com/rpgp/rpgp ).

  • Identify problems in objective-PGP
  • Look at RPGP
  • Test RPGP in the playground
  • Update and refactor crypto protocol
  • Add a new RPGP class
  • Use RPGP instead of Objective-PGP
  • Remove Objective-PGP dependencies. Can we still keep the original class?
Edited by cezipil