Issue #207 fix

I have fixed the #207 issue. (display key to be signed in CertifyKeyAcitivity)

Some notes:
  - The layout is same as for the signing key. (I may refactor it to be in a separate layout file) 
  - I have also added a string for the title, but only for english. I don't know how you deal with newly introduced stings.
  - This one for GSOC