Squashed commit of the following:
    commit 947842f9
    Date:   Thu May 8 18:36:14 2014 +0200
      final fixes before merging AutoSendEncrypted branch into the master
    commit 87dc3175
    Date:   Tue May 6 23:12:53 2014 +0200
      finishing first version of auto-send-encrypted and other sending stuff
    commit 17e0d58d
      persist encryption model
    commit 8dd0f8d2
    Date:   Mon May 5 23:41:56 2014 +0200
      try out convenient/manual settings for sending preferences
    commit 7fbae3e5
    Date:   Fri May 2 09:22:06 2014 +0200
      try to find valid keys inside enigmail
    commit 744fb1d3
      simplified accepted keys stuff
    commit 0d18ac6e
      option to accept only poersonal keys
    commit 91d1db2f
    Date:   Tue Apr 29 07:41:46 2014 +0200
      try different options for accepted keys
    commit 2cda0978
      reduced options and icons update while editing recipients
    commit 5da3971d
    Date:   Sun Apr 20 19:52:22 2014 +0200
      pre-commit hook to detect unexpanded tabs in changes
    commit aa9d2f65
      more conditions for confirmation before sending the final email
       replaces confirmBeforeSend by confirmBeforeSending
       migration from confirmBeforeSend to confirmBeforeSending MISSING
    commit 31916750
    Date:   Sun Apr 20 13:05:58 2014 +0200
      add feature AutoSendEncrypted (basic implementation)