Ensure b:GPGRecipients is initialized to a list value

Closes #18
Signed-off-by: James McCoy <vega.james@gmail.com>
Put --homedir at the start of the command line

Closes jamessan/vim-gnupg#20
Signed-off-by: James McCoy <vega.james@gmail.com>
Add g:GPGRecipientsMenu

Allow to set initial contents for recipients menu with
g:GPGRecipientsMenu. Example usage:

let g:GPGRecipientsMenu=""
    \."GPG: Example User <example@example.com>\<NL>"
    \."GPG: Other User <otherexample@example.com>\<NL>"
Refactor g:GPGRecipientsMenu to use list and rename to g:GPGPossibleRecipients

  let g:GPGPossibleRecipients=[
    \"Example User <example@example.com>",
    \"Other User <otherexample@example.com>"
  \]
Force Vim to re-setup the terminal after running a command

After Vim runs certain commands (e.g., pinentry-curses), the terminal is
not returned to its previous state.  This causes some escape sequences,
like arrow keys, to stop being recognized properly by Vim.

Re-setting &term to itself causes Vim to go through its normal terminal
initialization steps which gets things back in working order.

Closes jamessan/vim-gnupg#17
Signed-off-by: James McCoy <vega.james@gmail.com>
Merge pull request #21 from tyll/menu

Add g:GPGRecipientsMenu