packaging: Sign OS X app bundles in release script
core: Fix loading of old platform-location configuration files

Platform location configuration files created under the Torsion name
weren't properly loaded. Regression from c8d3f3a0
ui: Add PageView component

PageView displays one of a list of items, and switches between items
based on an associated key. This is useful for pages tied to a view's
selection.
ui: Separate non-window logic from ChatWindow into ChatPage
ui: Add optional combined chat window mode

Closes #19
core: Keep a permanent ConversationModel for each contact
core: Add unread count in ConversationModel
ui: Show unread message count on contact list
ui: Alert main window when messages arrive
ui: Clear history when closing ChatWindow in non-combined mode
ui: Add General preferences page and combined window setting
Merge pull request #61 from special/single-window

Implement optional combined window UI
ui: Fix "open in browser" dialog for single window mode
ui: Add options to hide the browser nagging dialog

The "open in browser" option on links opens a dialog, meant to warn
users away from using their default browser to open links where they
might want to preserve anonymity.

This commit changes that UI, and adds options to skip that dialog in the
future for links from the specific contact, or for links from all
contacts.
Merge pull request #62 from special/open-browser

Fix and improve "Open Browser" dialog
translation: Update translation source for 1.0.3 changes
core: Fix relative configuration paths on commandline

The current directory is reset at startup to the configuration path,
mostly as a matter of hygiene. If using a relative path from the
commandline, paths derived from it need to be relative to the new
current directory instead.
translation: Untranslate tor-related internal errors

There is no value in translating technical error strings; many of these
aren't shown to users, and when they are, their translated form won't be
of any more use. It just adds burden on translators.
tor: Clean up control command API

A lot of this API is really ugly. This makes it slightly less ugly.
Data replies are also handled correctly now, and error handling is
improved.
translation: Update spanish and italian translations

Contributions by strel and HostFat on Transifex.