Implement move commands in globals.py.  Add --redraw for bclose.
Conform to PEP 8.
Notify for unknown movement.
Merge branch '0.3.3-feature-movecmd-538'
add encryption function

This function takes a plaintext string and encryptes it with a given gpg key and
returns the encrypted text
add encrypt command

The encrypt command sets the encrypt flag of an envelope, which we will use to
later encrypt a message
create PGP/MIME mail, if encrypt flag is set

If the envelope has the encrypt flag set we encrypt the (signed if available)
mail and create a PGP/MIME compliant mail

TODOs:
a) create a 'This is a PGP/MIME encrypted mail...' warning on top of all
multipart parts

b) find the correct key for encryption

c) find a way to handle multiple recipients
add key parameter to encrypt command

We now can define the key, we want to encrypt with as parameter of the encrypt
command
add encrypt documentation
add unencrypt and toggleencrypt commands
pep8 corrections
add doc
give useful error message if key can't be found
move key dissolving to command

It is more useful if we check wether the key is available directly when the user
ask for encryption, rather than doing it before sending it
show whether the mail will be encrypted

We add a GPG encrypt line with the key to encrypt as description in the envelope
buffer
add docs for (un)encrypt
support multiple recipients in encryption

Multiple recipient-keys can be specified. They are shown in the envelope buffer.
A new command is introduced: 'rmencrypt' do remove a key from the encryption
lsit. Unfortunately pygpgme doesn't implement __cmp__() so we have to either
write something similar on our own or use this solution (index of the key in
encryption list)
rmencrypt now accepts keyids/hints instead of indices

We use an own has function for that, since pygpgme doesn't implement __cmp__()
or similar
automatically fill in recipients as encryption recipients

if the user doesn't supply encrypt with a list of encryption keys, the email
addresses of the email recipients are used
if all encryption keys are removed set flag to false

If all the encryption keys are deleted from the encryption list set the encrypt
flag in the enveleope to false