Merge pull request #38 from leif/master

new config item: IdleSecondsBeforeNotification
Handle Unicode autocomplete.

A patch to go.crypto/ssh/terminal[1] added support for Unicode input and
changed the autocomplete API accordingly. This change updates
xmpp-client to use the new API.

With this, inputting Unicode characters should mostly work, except that
grapheme clusters are know to have problems.

[1] https://code.google.com/p/go/source/detail?r=ff9ce887b46be1f2c2e72ebe3a7ee3f8645a63b6&repo=crypto

Fixes #39
Also filter 127 when printing to the terminal
Make fingerprint mismatches more prominent.

When starting an OTR session with a contact for whom one has fingerprint
saved, the message displayed when the resulting fingerprint is unknown
should be stronger than the case when no fingerprint is saved.
Add options to always encrypt conversations.

In order to prevent leakage, this change adds two config options:
AlwaysEncrypt and AlwaysEncryptWith. The former is a boolean that
controls whether unencrypted messages will ever be sent. The latter is a
list of Jabber uids to whom no unencrypted messages will ever be sent.
Add known .onion address for Calyx.

Fixes #42
display target uid in prompt